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Kamau A, Paton RS, Akech S, Mpimbaza A, Khazenzi C, Ogero M, Mumo E, Alegana VA, Agweyu A, Mturi N, Mohammed S, Bigogo G, Audi A, Kapisi J, Sserwanga A, Namuganga JF, Kariuki S, Otieno NA, Nyawanda BO, Olotu A, Salim N, Athuman T, Abdulla S, Mohamed AF, Mtove G, Reyburn H, Gupta S, Lourenço J, Bejon P, Snow RW. Malaria hospitalisation in East Africa: age, phenotype and transmission intensity. BMC Med 2022; 20:28. [PMID: 35081974 PMCID: PMC8793189 DOI: 10.1186/s12916-021-02224-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 12/21/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Understanding the age patterns of disease is necessary to target interventions to maximise cost-effective impact. New malaria chemoprevention and vaccine initiatives target young children attending routine immunisation services. Here we explore the relationships between age and severity of malaria hospitalisation versus malaria transmission intensity. METHODS Clinical data from 21 surveillance hospitals in East Africa were reviewed. Malaria admissions aged 1 month to 14 years from discrete administrative areas since 2006 were identified. Each site-time period was matched to a model estimated community-based age-corrected parasite prevalence to provide predictions of prevalence in childhood (PfPR2-10). Admission with all-cause malaria, severe malaria anaemia (SMA), respiratory distress (RD) and cerebral malaria (CM) were analysed as means and predicted probabilities from Bayesian generalised mixed models. RESULTS 52,684 malaria admissions aged 1 month to 14 years were described at 21 hospitals from 49 site-time locations where PfPR2-10 varied from < 1 to 48.7%. Twelve site-time periods were described as low transmission (PfPR2-10 < 5%), five low-moderate transmission (PfPR2-10 5-9%), 20 moderate transmission (PfPR2-10 10-29%) and 12 high transmission (PfPR2-10 ≥ 30%). The majority of malaria admissions were below 5 years of age (69-85%) and rare among children aged 10-14 years (0.7-5.4%) across all transmission settings. The mean age of all-cause malaria hospitalisation was 49.5 months (95% CI 45.1, 55.4) under low transmission compared with 34.1 months (95% CI 30.4, 38.3) at high transmission, with similar trends for each severe malaria phenotype. CM presented among older children at a mean of 48.7 months compared with 39.0 months and 33.7 months for SMA and RD, respectively. In moderate and high transmission settings, 34% and 42% of the children were aged between 2 and 23 months and so within the age range targeted by chemoprevention or vaccines. CONCLUSIONS Targeting chemoprevention or vaccination programmes to areas where community-based parasite prevalence is ≥10% is likely to match the age ranges covered by interventions (e.g. intermittent presumptive treatment in infancy to children aged 2-23 months and current vaccine age eligibility and duration of efficacy) and the age ranges of highest disease burden.
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Affiliation(s)
- Alice Kamau
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya.
| | | | - Samuel Akech
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya
| | - Arthur Mpimbaza
- Child Health and Development Centre, College of Health Sciences, Makerere University, Kampala, Uganda
| | - Cynthia Khazenzi
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya
| | - Morris Ogero
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya
| | - Eda Mumo
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya
| | - Victor A Alegana
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya
| | - Ambrose Agweyu
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya
| | - Neema Mturi
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Kilifi, Kenya
| | - Shebe Mohammed
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Kilifi, Kenya
| | - Godfrey Bigogo
- Kenya Medical Research Institute (KEMRI), Centre for Global Health Research, Kisumu, Kenya
| | - Allan Audi
- Kenya Medical Research Institute (KEMRI), Centre for Global Health Research, Kisumu, Kenya
| | - James Kapisi
- Infectious Diseases Research Collaboration, Kampala, Uganda
| | | | | | - Simon Kariuki
- Kenya Medical Research Institute (KEMRI), Centre for Global Health Research, Kisumu, Kenya
| | - Nancy A Otieno
- Kenya Medical Research Institute (KEMRI), Centre for Global Health Research, Kisumu, Kenya
| | - Bryan O Nyawanda
- Kenya Medical Research Institute (KEMRI), Centre for Global Health Research, Kisumu, Kenya
| | - Ally Olotu
- Ifakara Health Institute, Bagamoyo, Tanzania
| | - Nahya Salim
- Ifakara Health Institute, Bagamoyo, Tanzania
| | | | | | - Amina F Mohamed
- Kilimanjaro Christian Medical Centre/Joint Malaria Programme, Moshi, Tanzania
- London School of Hygiene and Tropical Medicine, London, UK
| | - George Mtove
- National Institute for Medical Research, Amani Research Centre, Muheza, Tanzania
| | - Hugh Reyburn
- London School of Hygiene and Tropical Medicine, London, UK
| | - Sunetra Gupta
- Department of Zoology, University of Oxford, Oxford, UK
| | - José Lourenço
- Department of Zoology, University of Oxford, Oxford, UK
| | - Philip Bejon
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Robert W Snow
- Kenya Medical Research Institute (KEMRI) - Wellcome Trust Research Programme, Nairobi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
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Paton RS, Kamau A, Akech S, Agweyu A, Ogero M, Mwandawiro C, Mturi N, Mohammed S, Mpimbaza A, Kariuki S, Otieno NA, Nyawanda BO, Mohamed AF, Mtove G, Reyburn H, Gupta S, Bejon P, Lourenço J, Snow RW. Malaria infection and severe disease risks in Africa. Science 2021; 373:926-931. [PMID: 34413238 PMCID: PMC7611598 DOI: 10.1126/science.abj0089] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 06/29/2021] [Indexed: 12/18/2022]
Abstract
The relationship between community prevalence of Plasmodium falciparum and the burden of severe, life-threatening disease remains poorly defined. To examine the three most common severe malaria phenotypes from catchment populations across East Africa, we assembled a dataset of 6506 hospital admissions for malaria in children aged 3 months to 9 years from 2006 to 2020. Admissions were paired with data from community parasite infection surveys. A Bayesian procedure was used to calibrate uncertainties in exposure (parasite prevalence) and outcomes (severe malaria phenotypes). Each 25% increase in prevalence conferred a doubling of severe malaria admission rates. Severe malaria remains a burden predominantly among young children (3 to 59 months) across a wide range of community prevalence typical of East Africa. This study offers a quantitative framework for linking malaria parasite prevalence and severe disease outcomes in children.
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Affiliation(s)
- Robert S Paton
- Department of Zoology, University of Oxford, Oxford, UK.
| | - Alice Kamau
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Nairobi, Kenya.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Samuel Akech
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Nairobi, Kenya
| | - Ambrose Agweyu
- Kilimanjaro Christian Medical Centre/Joint Malaria Programme, Moshi, Tanzania
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Nairobi, Kenya
| | - Morris Ogero
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Nairobi, Kenya
| | - Charles Mwandawiro
- Eastern and Southern Africa Centre of International Parasite Control, Kenya Medical Research Institute (KEMRI), Nairobi, Kenya
| | - Neema Mturi
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Shebe Mohammed
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Arthur Mpimbaza
- Child Health and Development Centre, Makerere University, College of Health Sciences, Kampala, Uganda
| | - Simon Kariuki
- Kenya Medical Research Institute (KEMRI)-Centre for Global Health Research, Kisumu, Kenya
| | - Nancy A Otieno
- Kenya Medical Research Institute (KEMRI)-Centre for Global Health Research, Kisumu, Kenya
| | - Bryan O Nyawanda
- Kenya Medical Research Institute (KEMRI)-Centre for Global Health Research, Kisumu, Kenya
| | - Amina F Mohamed
- Kilimanjaro Christian Medical Centre/Joint Malaria Programme, Moshi, Tanzania
- London School of Hygiene and Tropical Medicine, London, UK
| | - George Mtove
- National Institute for Medical Research, Amani Research Centre, Muheza, Tanzania
| | - Hugh Reyburn
- London School of Hygiene and Tropical Medicine, London, UK
| | - Sunetra Gupta
- Department of Zoology, University of Oxford, Oxford, UK
| | - Philip Bejon
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Kilifi, Kenya
| | - José Lourenço
- Department of Zoology, University of Oxford, Oxford, UK
| | - Robert W Snow
- Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Nairobi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
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Colmenero-Velázquez A, Esteso G, Del Rosal T, Calvo Apalategui A, Reyburn H, López-Granados E. Marked changes in innate immunity associated with a mild course of COVID-19 in identical twins with athymia and absent circulating T cells. J Allergy Clin Immunol 2020; 147:567-568. [PMID: 33309039 PMCID: PMC7713636 DOI: 10.1016/j.jaci.2020.11.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 10/08/2020] [Accepted: 11/12/2020] [Indexed: 11/18/2022]
Affiliation(s)
| | - Gloria Esteso
- Department of Immunology and Oncology, CNB-CSIC, Madrid, Spain
| | - Teresa Del Rosal
- Pediatric Infectious Diseases Department, La Paz University Hospital, Madrid, Spain; Pediatric Respiratory, Systemic and Neurological Infections & Host Immune Response Group, La Paz Institute of Biomedical Research, IdiPAZ, Madrid, Spain; Rare Disease Network Research Center (CIBERER U767), Madrid, Spain
| | | | - Hugh Reyburn
- Department of Immunology and Oncology, CNB-CSIC, Madrid, Spain
| | - Eduardo López-Granados
- Department of Immunology, La Paz University Hospital, Madrid, Spain; Rare Disease Network Research Center (CIBERER U767), Madrid, Spain; Lymphocyte Pathophysiology Group, La Paz Institute of Biomedical Research, IdiPAZ, Madrid, Spain.
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Mousa A, Al-Taiar A, Anstey NM, Badaut C, Barber BE, Bassat Q, Challenger JD, Cunnington AJ, Datta D, Drakeley C, Ghani AC, Gordeuk VR, Grigg MJ, Hugo P, John CC, Mayor A, Migot-Nabias F, Opoka RO, Pasvol G, Rees C, Reyburn H, Riley EM, Shah BN, Sitoe A, Sutherland CJ, Thuma PE, Unger SA, Viwami F, Walther M, Whitty CJM, William T, Okell LC. The impact of delayed treatment of uncomplicated P. falciparum malaria on progression to severe malaria: A systematic review and a pooled multicentre individual-patient meta-analysis. PLoS Med 2020; 17:e1003359. [PMID: 33075101 PMCID: PMC7571702 DOI: 10.1371/journal.pmed.1003359] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 08/26/2020] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Delay in receiving treatment for uncomplicated malaria (UM) is often reported to increase the risk of developing severe malaria (SM), but access to treatment remains low in most high-burden areas. Understanding the contribution of treatment delay on progression to severe disease is critical to determine how quickly patients need to receive treatment and to quantify the impact of widely implemented treatment interventions, such as 'test-and-treat' policies administered by community health workers (CHWs). We conducted a pooled individual-participant meta-analysis to estimate the association between treatment delay and presenting with SM. METHODS AND FINDINGS A search using Ovid MEDLINE and Embase was initially conducted to identify studies on severe Plasmodium falciparum malaria that included information on treatment delay, such as fever duration (inception to 22nd September 2017). Studies identified included 5 case-control and 8 other observational clinical studies of SM and UM cases. Risk of bias was assessed using the Newcastle-Ottawa scale, and all studies were ranked as 'Good', scoring ≥7/10. Individual-patient data (IPD) were pooled from 13 studies of 3,989 (94.1% aged <15 years) SM patients and 5,780 (79.6% aged <15 years) UM cases in Benin, Malaysia, Mozambique, Tanzania, The Gambia, Uganda, Yemen, and Zambia. Definitions of SM were standardised across studies to compare treatment delay in patients with UM and different SM phenotypes using age-adjusted mixed-effects regression. The odds of any SM phenotype were significantly higher in children with longer delays between initial symptoms and arrival at the health facility (odds ratio [OR] = 1.33, 95% CI: 1.07-1.64 for a delay of >24 hours versus ≤24 hours; p = 0.009). Reported illness duration was a strong predictor of presenting with severe malarial anaemia (SMA) in children, with an OR of 2.79 (95% CI:1.92-4.06; p < 0.001) for a delay of 2-3 days and 5.46 (95% CI: 3.49-8.53; p < 0.001) for a delay of >7 days, compared with receiving treatment within 24 hours from symptom onset. We estimate that 42.8% of childhood SMA cases and 48.5% of adult SMA cases in the study areas would have been averted if all individuals were able to access treatment within the first day of symptom onset, if the association is fully causal. In studies specifically recording onset of nonsevere symptoms, long treatment delay was moderately associated with other SM phenotypes (OR [95% CI] >3 to ≤4 days versus ≤24 hours: cerebral malaria [CM] = 2.42 [1.24-4.72], p = 0.01; respiratory distress syndrome [RDS] = 4.09 [1.70-9.82], p = 0.002). In addition to unmeasured confounding, which is commonly present in observational studies, a key limitation is that many severe cases and deaths occur outside healthcare facilities in endemic countries, where the effect of delayed or no treatment is difficult to quantify. CONCLUSIONS Our results quantify the relationship between rapid access to treatment and reduced risk of severe disease, which was particularly strong for SMA. There was some evidence to suggest that progression to other severe phenotypes may also be prevented by prompt treatment, though the association was not as strong, which may be explained by potential selection bias, sample size issues, or a difference in underlying pathology. These findings may help assess the impact of interventions that improve access to treatment.
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Affiliation(s)
- Andria Mousa
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
- * E-mail:
| | - Abdullah Al-Taiar
- School of Community & Environmental Health, College of Health Sciences, Old Dominion University, Norfolk, Virginia, United States of America
| | - Nicholas M. Anstey
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- Division of Medicine, Royal Darwin Hospital, Darwin, Northern Territory, Australia
| | - Cyril Badaut
- Unité de Biothérapie Infectieuse et Immunité, Institut de Recherche Biomédicale des Armées, Brétigny-sur-Orge, France
- Unité des Virus Emergents (UVE: Aix-Marseille Univ—IRD 190—Inserm 1207—IHU Méditerranée Infection), Marseille, France
| | - Bridget E. Barber
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Quique Bassat
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- ICREA, Barcelona, Spain
- Pediatric Infectious Diseases Unit, Pediatrics Department, Hospital Sant Joan de Déu (University of Barcelona), Barcelona, Spain
- Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | - Joseph D. Challenger
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Aubrey J. Cunnington
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, United Kingdom
| | - Dibyadyuti Datta
- Ryan White Center for Pediatric Infectious Disease and Global Health, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Chris Drakeley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Azra C. Ghani
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
| | - Victor R. Gordeuk
- Sickle Cell Center, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Matthew J. Grigg
- Global Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, Northern Territory, Australia
| | - Pierre Hugo
- Medicines for Malaria Venture, Geneva, Switzerland
| | - Chandy C. John
- Ryan White Center for Pediatric Infectious Disease and Global Health, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Alfredo Mayor
- ISGlobal, Hospital Clínic, Universitat de Barcelona, Barcelona, Spain
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
- Consorcio de Investigación Biomédica en Red de Epidemiología y Salud Pública (CIBERESP), Madrid, Spain
| | | | - Robert O. Opoka
- Department of Paediatrics and Child Health, Makerere University School of Medicine, Kampala, Uganda
| | - Geoffrey Pasvol
- Imperial College London, Department of Life Sciences, London, United Kingdom
| | - Claire Rees
- Centre for Global Public Health, Institute of Population Health Sciences, Barts & The London School of Medicine & Dentistry, London, United Kingdom
| | - Hugh Reyburn
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Eleanor M. Riley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Binal N. Shah
- Sickle Cell Center, Department of Medicine, University of Illinois at Chicago, Chicago, Illinois, United States of America
| | - Antonio Sitoe
- Centro de Investigação em Saúde de Manhiça (CISM), Maputo, Mozambique
| | - Colin J. Sutherland
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | | | - Stefan A. Unger
- Department of Child Life and Health, University of Edinburgh, United Kingdom
- Department of Respiratory Medicine, Royal Hospital for Sick Children, Edinburgh, United Kingdom
| | - Firmine Viwami
- Institut de Recherche Clinique du Bénin (IRCB), Cotonou, Benin
| | - Michael Walther
- Medical Research Council Unit, Fajara, The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia
| | - Christopher J. M. Whitty
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
- Gleneagles Hospital, Kota Kinabalu, Sabah, Malaysia
| | - Lucy C. Okell
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
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Elven J, Dahal P, Ashley EA, Thomas NV, Shrestha P, Stepniewska K, Crump JA, Newton PN, Bell D, Reyburn H, Hopkins H, Guérin PJ. Non-malarial febrile illness: a systematic review of published aetiological studies and case reports from Africa, 1980-2015. BMC Med 2020; 18:279. [PMID: 32951596 PMCID: PMC7504660 DOI: 10.1186/s12916-020-01744-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Accepted: 08/13/2020] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND The availability of reliable point-of-care tests for malaria has heralded a paradigm shift in the management of febrile illnesses away from presumptive antimalarial therapy. In the absence of a definitive diagnosis, health care providers are more likely to prescribe empirical antimicrobials to those who test negative for malaria. To improve management and guide further test development, better understanding is needed of the true causative agents and their geographic variability. METHODS A systematic review of published literature was undertaken to characterise the spectrum of pathogens causing non-malaria febrile illness in Africa (1980-2015). Literature searches were conducted in English and French languages in six databases: MEDLINE, EMBASE, Global Health (CABI), WHO Global Health Library, PASCAL, and Bulletin de la Société Française de Parasitologie (BDSP). Selection criteria included reporting on an infection or infections with a confirmed diagnosis, defined as pathogens detected in or cultured from samples from normally sterile sites, or serological evidence of current or past infection. A number of published articles (rather than incidence or prevalence) reporting a given pathogen were presented. RESULTS A total of 16,523 records from 48 African countries were screened, of which 1065 (6.4%) met selection criteria. Bacterial infections were reported in 564 (53.0%) records, viral infections in 374 (35.1%), parasitic infections in 47 (4.4%), fungal infections in nine (0.8%), and 71 (6.7%) publications reported more than one pathogen group. Age range of the study population was not specified in 233 (21.9%) publications. Staphylococcus aureus (18.2%), non-typhoidal Salmonella (17.3%), and Escherichia coli (15.4%) were the commonly reported bacterial infections whereas Rift Valley fever virus (7.4%), yellow fever virus (7.0%), and Ebola virus (6.7%) were the most commonly reported viral infections. Dengue virus infection, previously not thought to be widespread in Africa, was reported in 54 (5.1%) of articles. CONCLUSIONS This review summarises the published reports of non-malaria pathogens that may cause febrile illness in Africa. As the threat of antimicrobial resistance looms, knowledge of the distribution of infectious agents causing fever should facilitate priority setting in the development of new diagnostic tools and improved antimicrobial stewardship. TRIAL REGISTRATION PROSPERO, CRD42016049281.
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Affiliation(s)
- Jeanne Elven
- Infectious Diseases Data Observatory, University of Oxford, New Richards Building,Old Road Campus,Headington, Oxford, OX3 7LG, UK
| | - Prabin Dahal
- Infectious Diseases Data Observatory, University of Oxford, New Richards Building,Old Road Campus,Headington, Oxford, OX3 7LG, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Elizabeth A Ashley
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
- Lao-Oxford-Mahosot Hospital-Wellcome Research Unit, Mahosot Hospital, Vientiane, Laos
| | - Nigel V Thomas
- Infectious Diseases Data Observatory, University of Oxford, New Richards Building,Old Road Campus,Headington, Oxford, OX3 7LG, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Poojan Shrestha
- Infectious Diseases Data Observatory, University of Oxford, New Richards Building,Old Road Campus,Headington, Oxford, OX3 7LG, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Kasia Stepniewska
- Infectious Diseases Data Observatory, University of Oxford, New Richards Building,Old Road Campus,Headington, Oxford, OX3 7LG, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - John A Crump
- Centre for International Health, University of Otago, Dunedin, New Zealand
| | - Paul N Newton
- Infectious Diseases Data Observatory, University of Oxford, New Richards Building,Old Road Campus,Headington, Oxford, OX3 7LG, UK
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
- Lao-Oxford-Mahosot Hospital-Wellcome Research Unit, Mahosot Hospital, Vientiane, Laos
- London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - David Bell
- Independent consultant, Issaquah, Washington, USA
| | - Hugh Reyburn
- London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK
| | - Heidi Hopkins
- London School of Hygiene and Tropical Medicine, London, WC1E 7HT, UK.
| | - Philippe J Guérin
- Infectious Diseases Data Observatory, University of Oxford, New Richards Building,Old Road Campus,Headington, Oxford, OX3 7LG, UK.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.
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Ravenhall M, Campino S, Sepúlveda N, Manjurano A, Nadjm B, Mtove G, Wangai H, Maxwell C, Olomi R, Reyburn H, Drakeley CJ, Riley EM, Clark TG. Novel genetic polymorphisms associated with severe malaria and under selective pressure in North-eastern Tanzania. PLoS Genet 2018; 14:e1007172. [PMID: 29381699 PMCID: PMC5806895 DOI: 10.1371/journal.pgen.1007172] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Revised: 02/09/2018] [Accepted: 12/29/2017] [Indexed: 01/07/2023] Open
Abstract
Significant selection pressure has been exerted on the genomes of human populations exposed to Plasmodium falciparum infection, resulting in the acquisition of mechanisms of resistance against severe malarial disease. Many host genetic factors, including sickle cell trait, have been associated with reduced risk of developing severe malaria, but do not account for all of the observed phenotypic variation. Identification of novel inherited risk factors relies upon high-resolution genome-wide association studies (GWAS). We present findings of a GWAS of severe malaria performed in a Tanzanian population (n = 914, 15.2 million SNPs). Beyond the expected association with the sickle cell HbS variant, we identify protective associations within two interleukin receptors (IL-23R and IL-12RBR2) and the kelch-like protein KLHL3 (all P<10-6), as well as near significant effects for Major Histocompatibility Complex (MHC) haplotypes. Complementary analyses, based on detecting extended haplotype homozygosity, identified SYNJ2BP, GCLC and MHC as potential loci under recent positive selection. Through whole genome sequencing of an independent Tanzanian cohort (parent-child trios n = 247), we confirm the allele frequencies of common polymorphisms underlying associations and selection, as well as the presence of multiple structural variants that could be in linkage with these SNPs. Imputation of structural variants in a region encompassing the glycophorin genes on chromosome 4, led to the characterisation of more than 50 rare variants, and individually no strong evidence of associations with severe malaria in our primary dataset (P>0.3). Our approach demonstrates the potential of a joint genotyping-sequencing strategy to identify as-yet unknown susceptibility loci in an African population with well-characterised malaria phenotypes. The regions encompassing these loci are potential targets for the design of much needed interventions for preventing or treating malarial disease.
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Affiliation(s)
- Matt Ravenhall
- Pathogen Molecular Biology Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Susana Campino
- Pathogen Molecular Biology Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Nuno Sepúlveda
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Centre for Statistics and Applications, University of Lisbon, Lisbon, Portugal
| | - Alphaxard Manjurano
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
- National Institute for Medical Research, Mwanza, Tanzania
| | - Behzad Nadjm
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - George Mtove
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Hannah Wangai
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Caroline Maxwell
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Raimos Olomi
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Hugh Reyburn
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Christopher J. Drakeley
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Eleanor M. Riley
- Department of Immunology and Infection, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Taane G. Clark
- Pathogen Molecular Biology Department, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
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7
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Muro F, Meta J, Renju J, Mushi A, Mbakilwa H, Olomi R, Reyburn H, Hildenwall H. "It is good to take her early to the doctor" - mothers' understanding of childhood pneumonia symptoms and health care seeking in Kilimanjaro region, Tanzania. BMC Int Health Hum Rights 2017; 17:27. [PMID: 28938895 PMCID: PMC5610440 DOI: 10.1186/s12914-017-0135-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 09/17/2017] [Indexed: 11/24/2022]
Abstract
Background Pneumonia is among the leading causes of avoidable deaths for young children globally. The main burden of mortality falls on children from poor and rural families who are less likely to obtain the treatment they need, highlighting inequities in access to effective care and treatment. Caretakers’ illness perceptions and care-seeking practices are of major importance for children with pneumonia to receive adequate care. This study qualitatively explores the caretaker concepts of childhood pneumonia in relation to treatment seeking behaviour and health worker management in Moshi urban district, Tanzania. Methods In May - July 2013 data was gathered through different qualitative data collection techniques including five focus group discussions (FGDs) with mothers of children under-five years of age. The FGDs involved free listing of pneumonia symptoms and video presentations of children with respiratory symptoms done, these were triangulated with ten case narratives with mothers of children admitted with pneumonia and eleven in-depth interviews with hospital health workers. Transcripts were coded and analysed using qualitative content analysis. Results Mothers demonstrated good awareness of common childhood illnesses including pneumonia, which was often associated with symptoms such as cough, flu, chest tightness, fever, and difficulty in breathing. Mothers had mixed views on causative factors and treatments options but generally preferred modern medicine for persisting and severe symptoms. However, all respondent reported access to health facilities as a barrier to care, associated with transport, personal safety and economic constraints. Conclusion Local illness concepts and traditional treatment options did not constitute barriers to care for pneumonia symptoms. Poor access to health facilities was the main barrier. Decentralisation of care through community health workers may improve access to care but needs to be combined with strengthened referral systems and accessible hospital care for those in need.
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Affiliation(s)
- Florida Muro
- Kilimanjaro Christian Medical University College, P.O.Box 2240, Moshi, Tanzania. .,Kilimanjaro Christian Medical Centre, P.O.Box 3010, Moshi, Tanzania.
| | - Judith Meta
- Joint Malaria Programme - Kilimanjaro Christian Medical Centre, P.O.Box 2228, Moshi, Tanzania
| | - Jenny Renju
- Kilimanjaro Christian Medical University College, P.O.Box 2240, Moshi, Tanzania.,London School of Hygiene and Tropical Medicine (LSHTM), Keppel St, London, WICE7HT, UK
| | - Adiel Mushi
- The National Institute for Medical Research (NIMR), 3 Barack Obama Drive, P. O. Box 9653, 11101, Dar es Salaam, Tanzania
| | - Hilda Mbakilwa
- Joint Malaria Programme - Kilimanjaro Christian Medical Centre, P.O.Box 2228, Moshi, Tanzania
| | - Raimos Olomi
- Kilimanjaro Christian Medical University College, P.O.Box 2240, Moshi, Tanzania.,Kilimanjaro Christian Medical Centre, P.O.Box 3010, Moshi, Tanzania
| | - Hugh Reyburn
- Joint Malaria Programme - Kilimanjaro Christian Medical Centre, P.O.Box 2228, Moshi, Tanzania.,London School of Hygiene and Tropical Medicine (LSHTM), Keppel St, London, WICE7HT, UK
| | - Helena Hildenwall
- Department of Public Health Sciences, Global Health - Health System and Policy Research Group, Karolinska Institutet, SE-171 77, Stockholm, Sweden
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8
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Leffler EM, Band G, Busby GBJ, Kivinen K, Le QS, Clarke GM, Bojang KA, Conway DJ, Jallow M, Sisay-Joof F, Bougouma EC, Mangano VD, Modiano D, Sirima SB, Achidi E, Apinjoh TO, Marsh K, Ndila CM, Peshu N, Williams TN, Drakeley C, Manjurano A, Reyburn H, Riley E, Kachala D, Molyneux M, Nyirongo V, Taylor T, Thornton N, Tilley L, Grimsley S, Drury E, Stalker J, Cornelius V, Hubbart C, Jeffreys AE, Rowlands K, Rockett KA, Spencer CCA, Kwiatkowski DP. Resistance to malaria through structural variation of red blood cell invasion receptors. Science 2017; 356:science.aam6393. [PMID: 28522690 DOI: 10.1126/science.aam6393] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 05/08/2017] [Indexed: 12/29/2022]
Abstract
The malaria parasite Plasmodium falciparum invades human red blood cells by a series of interactions between host and parasite surface proteins. By analyzing genome sequence data from human populations, including 1269 individuals from sub-Saharan Africa, we identify a diverse array of large copy-number variants affecting the host invasion receptor genes GYPA and GYPB We find that a nearby association with severe malaria is explained by a complex structural rearrangement involving the loss of GYPB and gain of two GYPB-A hybrid genes, which encode a serologically distinct blood group antigen known as Dantu. This variant reduces the risk of severe malaria by 40% and has recently increased in frequency in parts of Kenya, yet it appears to be absent from west Africa. These findings link structural variation of red blood cell invasion receptors with natural resistance to severe malaria.
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Affiliation(s)
- Ellen M Leffler
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.,Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Gavin Band
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.,Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - George B J Busby
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Katja Kivinen
- Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Quang Si Le
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Geraldine M Clarke
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Kalifa A Bojang
- Medical Research Council Unit, Atlantic Boulevard, Fajara, Post Office Box 273, The Gambia
| | - David J Conway
- Medical Research Council Unit, Atlantic Boulevard, Fajara, Post Office Box 273, The Gambia.,Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Muminatou Jallow
- Medical Research Council Unit, Atlantic Boulevard, Fajara, Post Office Box 273, The Gambia.,Royal Victoria Teaching Hospital, Independence Drive, Post Office Box 1515, Banjul, The Gambia
| | - Fatoumatta Sisay-Joof
- Medical Research Council Unit, Atlantic Boulevard, Fajara, Post Office Box 273, The Gambia
| | - Edith C Bougouma
- Centre National de Recherche et de Formation sur le Paludisme (CNRFP), 01 BP 2208 Ouagadougou 01, Burkina Faso
| | | | - David Modiano
- University of Rome La Sapienza, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Sodiomon B Sirima
- Centre National de Recherche et de Formation sur le Paludisme (CNRFP), 01 BP 2208 Ouagadougou 01, Burkina Faso
| | - Eric Achidi
- Department of Medical Laboratory Sciences, University of Buea, Post Office Box 63, Buea, South West Region, Cameroon
| | - Tobias O Apinjoh
- Department of Biochemistry and Molecular Biology, University of Buea, Post Office Box 63, Buea, South West Region, Cameroon
| | - Kevin Marsh
- Kenyan Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Post Office Box 230-80108, Kilifi, Kenya.,Nuffield Department of Medicine, NDM Research Building, Roosevelt Drive, Headington, Oxford OX3 7FZ, UK
| | - Carolyne M Ndila
- Kenyan Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Post Office Box 230-80108, Kilifi, Kenya
| | - Norbert Peshu
- Kenyan Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Post Office Box 230-80108, Kilifi, Kenya
| | - Thomas N Williams
- Kenyan Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Post Office Box 230-80108, Kilifi, Kenya.,Faculty of Medicine, Department of Medicine, Imperial College, Exhibition Road, London SW7 2AZ, UK
| | - Chris Drakeley
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Post Office Box 2228, Moshi, Tanzania.,Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Alphaxard Manjurano
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Post Office Box 2228, Moshi, Tanzania.,Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK.,National Institute for Medical Research, Mwanza Research Centre, Mwanza City, Tanzania
| | - Hugh Reyburn
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Post Office Box 2228, Moshi, Tanzania.,Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Eleanor Riley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - David Kachala
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, College of Medicine, Post Office Box 30096, Chichiri, Blantyre 3, Malawi
| | - Malcolm Molyneux
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, College of Medicine, Post Office Box 30096, Chichiri, Blantyre 3, Malawi.,Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Vysaul Nyirongo
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Queen Elizabeth Central Hospital, College of Medicine, Post Office Box 30096, Chichiri, Blantyre 3, Malawi
| | - Terrie Taylor
- Blantyre Malaria Project, Queen Elizabeth Central Hospital, College of Medicine, Post Office Box 30096, Chichiri, Blantyre 3, Malawi.,College of Osteopathic Medicine, Michigan State University, East Lansing, MI 48824, USA
| | - Nicole Thornton
- International Blood Group Reference Laboratory, National Health Service (NHS) Blood and Transplant, 500 North Bristol Park, Filton, Bristol BS34 7QH, UK
| | - Louise Tilley
- International Blood Group Reference Laboratory, National Health Service (NHS) Blood and Transplant, 500 North Bristol Park, Filton, Bristol BS34 7QH, UK
| | - Shane Grimsley
- International Blood Group Reference Laboratory, National Health Service (NHS) Blood and Transplant, 500 North Bristol Park, Filton, Bristol BS34 7QH, UK
| | - Eleanor Drury
- Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Jim Stalker
- Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Victoria Cornelius
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Christina Hubbart
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Anna E Jeffreys
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Kate Rowlands
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK
| | - Kirk A Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.,Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
| | - Chris C A Spencer
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK.
| | - Dominic P Kwiatkowski
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK. .,Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK
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9
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Hopkins H, Bruxvoort KJ, Cairns ME, Chandler CIR, Leurent B, Ansah EK, Baiden F, Baltzell KA, Björkman A, Burchett HED, Clarke SE, DiLiberto DD, Elfving K, Goodman C, Hansen KS, Kachur SP, Lal S, Lalloo DG, Leslie T, Magnussen P, Jefferies LM, Mårtensson A, Mayan I, Mbonye AK, Msellem MI, Onwujekwe OE, Owusu-Agyei S, Reyburn H, Rowland MW, Shakely D, Vestergaard LS, Webster J, Wiseman VL, Yeung S, Schellenberg D, Staedke SG, Whitty CJM. Impact of introduction of rapid diagnostic tests for malaria on antibiotic prescribing: analysis of observational and randomised studies in public and private healthcare settings. BMJ 2017; 356:j1054. [PMID: 28356302 PMCID: PMC5370398 DOI: 10.1136/bmj.j1054] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/06/2017] [Indexed: 01/21/2023]
Abstract
Objectives To examine the impact of use of rapid diagnostic tests for malaria on prescribing of antimicrobials, specifically antibiotics, for acute febrile illness in Africa and Asia.Design Analysisof nine preselected linked and codesigned observational and randomised studies (eight cluster or individually randomised trials and one observational study).Setting Public and private healthcare settings, 2007-13, in Afghanistan, Cameroon, Ghana, Nigeria, Tanzania, and Uganda.Participants 522 480 children and adults with acute febrile illness.Interventions Rapid diagnostic tests for malaria.Main outcome measures Proportions of patients for whom an antibiotic was prescribed in trial groups who had undergone rapid diagnostic testing compared with controls and in patients with negative test results compared with patients with positive results. A secondary aim compared classes of antibiotics prescribed in different settings.Results Antibiotics were prescribed to 127 052/238 797 (53%) patients in control groups and 167 714/283 683 (59%) patients in intervention groups. Antibiotics were prescribed to 40% (35 505/89 719) of patients with a positive test result for malaria and to 69% (39 400/57 080) of those with a negative result. All but one study showed a trend toward more antibiotic prescribing in groups who underwent rapid diagnostic tests. Random effects meta-analysis of the trials showed that the overall risk of antibiotic prescription was 21% higher (95% confidence interval 7% to 36%) in intervention settings. In most intervention settings, patients with negative test results received more antibiotic prescriptions than patients with positive results for all the most commonly used classes: penicillins, trimethoprim-sulfamethoxazole (one exception), tetracyclines, and metronidazole.Conclusions Introduction of rapid diagnostic tests for malaria to reduce unnecessary use of antimalarials-a beneficial public health outcome-could drive up untargeted use of antibiotics. That 69% of patients were prescribed antibiotics when test results were negative probably represents overprescription.This included antibiotics from several classes, including those like metronidazole that are seldom appropriate for febrile illness, across varied clinical, health system, and epidemiological settings. It is often assumed that better disease specific diagnostics will reduce antimicrobial overuse, but they might simply shift it from one antimicrobial class to another. Current global implementation of malaria testing might increase untargeted antibiotic use and must be examined.
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Affiliation(s)
- Heidi Hopkins
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | | | - Matthew E Cairns
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | | | - Baptiste Leurent
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | | | | | | | | | | | - Siân E Clarke
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | | | | | | | - Kristian S Hansen
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
- University of Copenhagen, Copenhagen, DK1014, Denmark
| | | | - Sham Lal
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | | | - Toby Leslie
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
- Health Protection Research Organisation, Kabul, Afghanistan
| | - Pascal Magnussen
- Centre for Medical Parasitology, University of Copenhagen and Copenhagen University Hospital, and Department for Veterinary Disease Biology, University of Copenhagen, Copenhagen, Denmark
| | | | | | - Ismail Mayan
- Health Protection Research Organisation, Kabul, Afghanistan
| | - Anthony K Mbonye
- Ministry of Health, Kampala, Uganda
- Makerere University School of Public Health, Kampala, Uganda
| | | | - Obinna E Onwujekwe
- Department of Pharmacology and Therapeutics, University of Nigeria, Enugu, Nigeria
| | - Seth Owusu-Agyei
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
- Kintampo Health Research Centre, Kintampo, Ghana
| | - Hugh Reyburn
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Mark W Rowland
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Delér Shakely
- Centre for Malaria Research, Karolinska Institutet, Stockholm, Sweden, and Health Metrics at Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Lasse S Vestergaard
- Department of Infectious Disease Epidemiology, Statens Serum Institut, Copenhagen, Denmark
| | - Jayne Webster
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | - Virginia L Wiseman
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
- School of Public Health and Community Medicine, University of New South Wales, Sydney, Australia
| | - Shunmay Yeung
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
| | | | - Sarah G Staedke
- London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
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10
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Muro F, Mosha N, Hildenwall H, Mtei F, Harrison N, Schellenberg D, Olomi R, Reyburn H, Todd J. Variability of respiratory rate measurements in children suspected with non-severe pneumonia in north-east Tanzania. Trop Med Int Health 2017; 22:139-147. [PMID: 27862739 PMCID: PMC5299505 DOI: 10.1111/tmi.12814] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Measurement of respiratory rate is an important clinical sign in the diagnosis of pneumonia but suffers from interobserver variation. Here, we assess the use of video recordings as a quality assurance tool that could be useful both in research and in training of staff. METHODS Respiratory rates (RR) were recorded in children aged 2-59 months presenting with cough or difficulty breathing at two busy outpatient clinics in Tanzania. Measurements were repeated at 10-min intervals in a quiet environment with simultaneous video recordings that were independently reviewed by two paediatricians. RESULTS Eight hundred and fifty-nine videos were sent to two paediatricians; 148 (17.2%) were considered unreadable by one or both. For the 711 (82.8%) videos that were readable by both paediatricians, there was perfect agreement for the presence of raised RR with a kappa value (κ) of 0.85 (P < 0.001); and in 476 (66.9%) cases, both paediatricians agreed on the RR within 2 breaths per minute (±2 bpm). A reported illness of 5 days or more was associated with unreadable video recordings (OR = 3.44, CI: 1.5-6.08; P < 0.001). The multilevel model showed that differences between observers accounted for only 13% of the variability in RR. CONCLUSION Video recordings are reliable tools for quality assurance of RR measurements in children with suspected pneumonia. Videos with a clear view of respiratory movements may also be useful in training primary healthcare staff.
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Affiliation(s)
- Florida Muro
- Kilimanjaro Christian Medical University CollegeMoshiTanzania
- Kilimanjaro Christian Medical CentreMoshiTanzania
| | - Neema Mosha
- Kilimanjaro Christian Medical University CollegeMoshiTanzania
| | - Helena Hildenwall
- Global Health – Health System and Policy Research GroupKarolinska InstitutetStockholmSweden
| | - Frank Mtei
- Joint Malaria ProgrammeKilimanjaro Christian Medical CentreMoshiTanzania
| | - Nicole Harrison
- Department of Medicine IMedical University of ViennaViennaAustria
- London School of Hygiene & Tropical MedicineLondonUK
| | | | - Raimos Olomi
- Kilimanjaro Christian Medical University CollegeMoshiTanzania
- Kilimanjaro Christian Medical CentreMoshiTanzania
| | - Hugh Reyburn
- Joint Malaria ProgrammeKilimanjaro Christian Medical CentreMoshiTanzania
- London School of Hygiene & Tropical MedicineLondonUK
| | - Jim Todd
- Kilimanjaro Christian Medical University CollegeMoshiTanzania
- London School of Hygiene & Tropical MedicineLondonUK
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11
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Clarke GM, Rockett K, Kivinen K, Hubbart C, Jeffreys AE, Rowlands K, Jallow M, Conway DJ, Bojang KA, Pinder M, Usen S, Sisay-Joof F, Sirugo G, Toure O, Thera MA, Konate S, Sissoko S, Niangaly A, Poudiougou B, Mangano VD, Bougouma EC, Sirima SB, Modiano D, Amenga-Etego LN, Ghansah A, Koram KA, Wilson MD, Enimil A, Evans J, Amodu OK, Olaniyan S, Apinjoh T, Mugri R, Ndi A, Ndila CM, Uyoga S, Macharia A, Peshu N, Williams TN, Manjurano A, Sepúlveda N, Clark TG, Riley E, Drakeley C, Reyburn H, Nyirongo V, Kachala D, Molyneux M, Dunstan SJ, Phu NH, Quyen NN, Thai CQ, Hien TT, Manning L, Laman M, Siba P, Karunajeewa H, Allen S, Allen A, Davis TME, Michon P, Mueller I, Molloy SF, Campino S, Kerasidou A, Cornelius VJ, Hart L, Shah SS, Band G, Spencer CCA, Agbenyega T, Achidi E, Doumbo OK, Farrar J, Marsh K, Taylor T, Kwiatkowski DP. Characterisation of the opposing effects of G6PD deficiency on cerebral malaria and severe malarial anaemia. eLife 2017; 6:e15085. [PMID: 28067620 PMCID: PMC5222559 DOI: 10.7554/elife.15085] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 11/03/2016] [Indexed: 01/27/2023] Open
Abstract
Glucose-6-phosphate dehydrogenase (G6PD) deficiency is believed to confer protection against Plasmodium falciparum malaria, but the precise nature of the protective effecthas proved difficult to define as G6PD deficiency has multiple allelic variants with different effects in males and females, and it has heterogeneous effects on the clinical outcome of P. falciparum infection. Here we report an analysis of multiple allelic forms of G6PD deficiency in a large multi-centre case-control study of severe malaria, using the WHO classification of G6PD mutations to estimate each individual's level of enzyme activity from their genotype. Aggregated across all genotypes, we find that increasing levels of G6PD deficiency are associated with decreasing risk of cerebral malaria, but with increased risk of severe malarial anaemia. Models of balancing selection based on these findings indicate that an evolutionary trade-off between different clinical outcomes of P. falciparum infection could have been a major cause of the high levels of G6PD polymorphism seen in human populations.
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Affiliation(s)
- Geraldine M Clarke
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom,MRC Centre for Genomics and Global Health, University of Oxford, Oxford, United Kingdom, (GMC)
| | - Kirk Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom,MRC Centre for Genomics and Global Health, University of Oxford, Oxford, United Kingdom,The Wellcome Trust Sanger Institute, Cambridge, United Kingdom, (KRoc)
| | - Katja Kivinen
- The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | - Christina Hubbart
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Anna E Jeffreys
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Kate Rowlands
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Muminatou Jallow
- Medical Research Council Unit The Gambia, Fajara, Gambia,Edward Francis Small Teaching Hospital, Independence Drive, Banjul, Gambia
| | - David J Conway
- Medical Research Council Unit The Gambia, Fajara, Gambia,Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | - Stanley Usen
- Medical Research Council Unit The Gambia, Fajara, Gambia
| | | | - Giorgio Sirugo
- Medical Research Council Unit The Gambia, Fajara, Gambia
| | - Ousmane Toure
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | - Mahamadou A Thera
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | - Salimata Konate
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | - Sibiry Sissoko
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | - Amadou Niangaly
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | - Belco Poudiougou
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | | | - Edith C Bougouma
- Centre National de Recherche et de Formation sur le Paludisme (CNRFP), Ouagadougou, Burkina Faso
| | - Sodiomon B Sirima
- Centre National de Recherche et de Formation sur le Paludisme (CNRFP), Ouagadougou, Burkina Faso
| | | | | | - Anita Ghansah
- Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Kwadwo A Koram
- Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Michael D Wilson
- Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | | | - Jennifer Evans
- Department of Molecular Medicine, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany,Kumasi Centre for Collaborative Research, Kumasi, Ghana
| | | | | | - Tobias Apinjoh
- Department of Biochemistry and Molecular Biology, University of Buea, Buea, Cameroon
| | - Regina Mugri
- Department of Medical Laboratory Sciences, University of Buea, Buea, Cameroon
| | - Andre Ndi
- Department of Medical Laboratory Sciences, University of Buea, Buea, Cameroon
| | | | - Sophie Uyoga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Norbert Peshu
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Thomas N Williams
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya,Department of Medicine, Faculty of Medicine, Imperial College, London, United Kingdom
| | - Alphaxard Manjurano
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania,Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Nuno Sepúlveda
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Taane G Clark
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom,Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Eleanor Riley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Chris Drakeley
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania,Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Hugh Reyburn
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania,Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Vysaul Nyirongo
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, University of Malawi, Blantyre, Malawi
| | - David Kachala
- Oxford University Clinical Research Unit, University of Oxford, Ho Chi Minh City, Vietnam
| | - Malcolm Molyneux
- Malawi-Liverpool Wellcome Trust Clinical Research Programme, University of Malawi, Blantyre, Malawi,Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, United Kingdom
| | - Sarah J Dunstan
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Australia
| | - Nguyen Hoan Phu
- Oxford University Clinical Research Unit, University of Oxford, Ho Chi Minh City, Vietnam,Hospital for Tropical Diseases, Ho Chi Minh City, Viet Nam
| | - Nguyen Ngoc Quyen
- Oxford University Clinical Research Unit, University of Oxford, Ho Chi Minh City, Vietnam
| | - Cao Quang Thai
- Oxford University Clinical Research Unit, University of Oxford, Ho Chi Minh City, Vietnam,Hospital for Tropical Diseases, Ho Chi Minh City, Viet Nam
| | - Tran Tinh Hien
- Oxford University Clinical Research Unit, University of Oxford, Ho Chi Minh City, Vietnam,Hospital for Tropical Diseases, Ho Chi Minh City, Viet Nam,Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Laurens Manning
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Moses Laman
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | - Peter Siba
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea
| | | | | | - Angela Allen
- Weatherall Institute of Molecular Medicine, Oxford University, Oxford, United Kingdom
| | | | - Pascal Michon
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea,Faculty of Medicine and Health Sciences, Divine Word University, Madang, Papua New Guinea
| | - Ivo Mueller
- Papua New Guinea Institute of Medical Research, Goroka, Papua New Guinea,Walter and Eliza Hall Institute of Medical Research, Melbourne, Australia,Barcelona Centre for International Health Research, Barcelona, Spain
| | - Síle F Molloy
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Susana Campino
- The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
| | - Angeliki Kerasidou
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom,Nuffield Department of Population Health, The Ethox Centre, University of Oxford, Oxford, United Kingdom
| | - Victoria J Cornelius
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom,MRC Centre for Genomics and Global Health, University of Oxford, Oxford, United Kingdom
| | - Lee Hart
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Shivang S Shah
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom,Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, United States
| | - Gavin Band
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom,MRC Centre for Genomics and Global Health, University of Oxford, Oxford, United Kingdom
| | - Chris CA Spencer
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Tsiri Agbenyega
- Komfo Anoyke Teaching Hospital, Kumasi, Ghana,Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Eric Achidi
- Department of Medical Laboratory Sciences, University of Buea, Buea, Cameroon
| | - Ogobara K Doumbo
- Malaria Research and Training Centre, University of Bamako, Bamako, Mali
| | - Jeremy Farrar
- Oxford University Clinical Research Unit, University of Oxford, Ho Chi Minh City, Vietnam,Nuffield Department of Clinical Medicine, Center for Tropical Medicine, Oxford University, Oxford, United Kingdom
| | - Kevin Marsh
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Terrie Taylor
- Blantyre Malaria Project at the College of Medicine, University of Malawi, Blantyre, Malawi
| | - Dominic P Kwiatkowski
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom,MRC Centre for Genomics and Global Health, University of Oxford, Oxford, United Kingdom,The Wellcome Trust Sanger Institute, Cambridge, United Kingdom, (DPK)
| | - MalariaGEN Consortium
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom,The Wellcome Trust Sanger Institute, Cambridge, United Kingdom
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12
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Hildenwall H, Muro F, Jansson J, Mtove G, Reyburn H, Amos B. Point-of-care assessment of C-reactive protein and white blood cell count to identify bacterial aetiologies in malaria-negative paediatric fevers in Tanzania. Trop Med Int Health 2016; 22:286-293. [PMID: 27935664 PMCID: PMC5336187 DOI: 10.1111/tmi.12823] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Objective To assess the role of point‐of‐care (PoC) assessment of C‐reactive protein (CRP) and white blood cell (WBC) count to identify bacterial illness in Tanzanian children with non‐severe non‐malarial fever. Methods From the outpatient department of a district hospital in Tanzania, 428 patients between 3 months and 5 years of age who presented with fever and a negative malaria test were enrolled. All had a physical examination and bacterial cultures from blood and urine. Haemoglobin, CRP and WBC were measured by PoC devices. Results Positive blood cultures were detected in 6/428 (1.4%) children and urine cultures were positive in 24/401 (6.0%). Mean WBC was similar in children with or without bacterial illness (14.0 × 109, 95% CI 12.0–16.0 × 109 vs. 12.0 × 109, 95% CI 11.4–12.7 × 109), while mean CRP was higher in children with bacterial illness (41.0 mg/l, 95% CI 28.3–53.6 vs. 23.8 mg/l, 95% CI 17.8–27.8). In ROC analysis, the optimum cut‐off value for CRP to identify bacterial illness was 19 mg/l but with an area under the curve of only 0.62. Negative predictive values exceeded 80%, while positive predictive values were under 40%. Conclusion WBC and CRP levels had limited value in identifying children with bacterial infections. The positive predictive values for both tests were too low to be used as single tools for treatment decisions.
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Affiliation(s)
- Helena Hildenwall
- Global Health, Health Systems and Policy, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden.,Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - Florida Muro
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Jaqueline Jansson
- Global Health, Health Systems and Policy, Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden
| | - George Mtove
- Joint Malaria Programme, St Augustine's Hospital, Muheza, Tanzania.,National Institute for Medical Research, Amani Centre, Muheza, Tanga, Tanzania
| | - Hugh Reyburn
- London School of Hygiene and Tropical Medicine, London, UK
| | - Ben Amos
- Joint Malaria Programme, St Augustine's Hospital, Muheza, Tanzania
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13
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Chandler CIR, Burchett H, Boyle L, Achonduh O, Mbonye A, DiLiberto D, Reyburn H, Onwujekwe O, Haaland A, Roca-Feltrer A, Baiden F, Mbacham WF, Ndyomugyenyi R, Nankya F, Mangham-Jefferies L, Clarke S, Mbakilwa H, Reynolds J, Lal S, Leslie T, Maiteki-Sebuguzi C, Webster J, Magnussen P, Ansah E, Hansen KS, Hutchinson E, Cundill B, Yeung S, Schellenberg D, Staedke SG, Wiseman V, Lalloo DG, Whitty CJM. Examining Intervention Design: Lessons from the Development of Eight Related Malaria Health Care Intervention Studies. Health Syst Reform 2016; 2:373-388. [PMID: 31514719 PMCID: PMC6176770 DOI: 10.1080/23288604.2016.1179086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract—Rigorous evidence of “what works” to improve health care is in demand, but methods for the development of interventions have not been scrutinized in the same ways as methods for evaluation. This article presents and examines intervention development processes of eight malaria health care interventions in East and West Africa. A case study approach was used to draw out experiences and insights from multidisciplinary teams who undertook to design and evaluate these studies. Four steps appeared necessary for intervention design: (1) definition of scope, with reference to evaluation possibilities; (2) research to inform design, including evidence and theory reviews and empirical formative research; (3) intervention design, including consideration and selection of approaches and development of activities and materials; and (4) refining and finalizing the intervention, incorporating piloting and pretesting. Alongside these steps, projects produced theories, explicitly or implicitly, about (1) intended pathways of change and (2) how their intervention would be implemented.The work required to design interventions that meet and contribute to current standards of evidence should not be underestimated. Furthermore, the process should be recognized not only as technical but as the result of micro and macro social, political, and economic contexts, which should be acknowledged and documented in order to infer generalizability. Reporting of interventions should go beyond descriptions of final intervention components or techniques to encompass the development process. The role that evaluation possibilities play in intervention design should be brought to the fore in debates over health care improvement.
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Affiliation(s)
- Clare I R Chandler
- Department of Global Health and Development , London School of Hygiene & Tropical Medicine , London , UK
| | - Helen Burchett
- Department of Global Health and Development , London School of Hygiene & Tropical Medicine , London , UK
| | - Louise Boyle
- Department of Global Health and Development , London School of Hygiene & Tropical Medicine , London , UK
| | - Olivia Achonduh
- Laboratory for Public Health Research Biotechnologies, The Biotechnology Center, University of Yaoundé I , Yaoundé , Cameroon
| | - Anthony Mbonye
- School of Public Health-Makerere University & Commissioner Health Services, Ministry of Health , Kampala , Uganda
| | - Deborah DiLiberto
- Clinical Research Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Hugh Reyburn
- Disease Control Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Obinna Onwujekwe
- Department of Pharmacology and Therapeutics , University of Nigeria Enugu-Campus , Enugu , Nigeria
| | - Ane Haaland
- Institute of Health and Society , Department of Community Medicine , Blindern , Oslo , Norway
| | | | - Frank Baiden
- Malaria Group, Kintampo Health Research Centre , Kintampo , Ghana
| | - Wilfred F Mbacham
- Laboratory for Public Health Research Biotechnologies, The Biotechnology Center, University of Yaoundé I , Yaoundé , Cameroon
| | | | - Florence Nankya
- Infectious Diseases Research Collaboration , Kampala , Uganda
| | - Lindsay Mangham-Jefferies
- Department of Global Health and Development , London School of Hygiene & Tropical Medicine , London , UK
| | - Sian Clarke
- Disease Control Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Hilda Mbakilwa
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre , Moshi , Tanzania
| | - Joanna Reynolds
- Department of Global Health and Development , London School of Hygiene & Tropical Medicine , London , UK
| | - Sham Lal
- Disease Control Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Toby Leslie
- Disease Control Department , London School of Hygiene & Tropical Medicine , London , UK
| | | | - Jayne Webster
- Disease Control Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Pascal Magnussen
- Centre for Medical Parasitology, Faculty of Health and Medical Sciences, University of Copenhagen , Copenhagen , Denmark
| | - Evelyn Ansah
- Dangme West District Health Directorate, Ghana Health Service , Dodowa , Ghana
| | - Kristian S Hansen
- Department of Global Health and Development , London School of Hygiene & Tropical Medicine , London , UK
| | - Eleanor Hutchinson
- Department of Global Health and Development , London School of Hygiene & Tropical Medicine , London , UK
| | - Bonnie Cundill
- Disease Control Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Shunmay Yeung
- Department of Global Health and Development , London School of Hygiene & Tropical Medicine , London , UK
| | - David Schellenberg
- Disease Control Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Sarah G Staedke
- Disease Control Department , London School of Hygiene & Tropical Medicine , London , UK
| | - Virginia Wiseman
- Department of Global Health and Development , London School of Hygiene & Tropical Medicine , London , UK.,School of Public Health and Community Medicine , Kensington , New South Wales , Australia
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14
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Michael D, Kezakubi D, Juma A, Todd J, Reyburn H, Renju J. The feasibility and acceptability of screening for hypertension in private drug retail outlets: a pilot study in Mwanza region, Tanzania. Int Health 2016; 8:360-6. [PMID: 27170761 PMCID: PMC5039818 DOI: 10.1093/inthealth/ihw023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 03/10/2016] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Hypertension is a major contributor to ill health in sub-Saharan Africa. Developing countries need to increase access for screening. This study assesses the feasibility and acceptability of using private sector drug retail outlets to screen for hypertension in Mwanza region, Tanzania. METHODS A pilot study took place in eight drug retail outlets from August 2013 to February 2014. Customers ≥18 years were invited for screening. Socio-demographic characteristics, hypertension knowledge, hypertension screening and treatment history were collected. Subjects with systolic blood pressure over 140 mmHg were referred for follow up. Referral slips captured attendance. Mystery client visits and follow up phone calls were conducted to assess service quality. RESULTS A total of 971 customers were screened, one person refused; 109 (11.2%) had blood pressure over 140/90 mmHg and were referred for ongoing assessment; 85/109 (78.0%) were newly diagnosed. Customers reported that the service was acceptable. Service providers were able to follow the protocol. Only 18/85 (21%) newly diagnosed participants visited the referral clinic within two weeks. CONCLUSIONS Blood pressure screening was feasible and acceptable to customers of private drug retail outlets. However many who were referred failed to attend at a referral centre and further research is needed in this area.
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Affiliation(s)
- Denna Michael
- National Institute of Medical Research, Isamilo Road, P.O. Box 1462, Mwanza, Tanzania
| | - Dotto Kezakubi
- National Institute of Medical Research, Isamilo Road, P.O. Box 1462, Mwanza, Tanzania
| | - Adinan Juma
- Kilimanjaro Christian Medical University College (Tumaini University), Department of Epidemiology and Biostatistics, P.O. Box 2240, Moshi, Tanzania
| | - Jim Todd
- The London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Hugh Reyburn
- The London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Jenny Renju
- Kilimanjaro Christian Medical University College (Tumaini University), Department of Epidemiology and Biostatistics, P.O. Box 2240, Moshi, Tanzania The London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
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15
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Fernández-Escobar M, Baldanta S, Reyburn H, Guerra S. Use of functional genomics to understand replication deficient poxvirus-host interactions. Virus Res 2016; 216:1-15. [PMID: 26519757 DOI: 10.1016/j.virusres.2015.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 10/06/2015] [Accepted: 10/07/2015] [Indexed: 10/22/2022]
Abstract
High-throughput genomics technologies are currently being used to study a wide variety of viral infections, providing insight into which cellular genes and pathways are regulated after infection, and how these changes are related, or not, to efficient elimination of the pathogen. This article will focus on how gene expression studies of infections with non-replicative poxviruses currently used as vaccine vectors provide a global perspective of the molecular events associated with the viral infection in human cells. These high-throughput genomics approaches have the potential to lead to the identification of specific new properties of the viral vector or novel cellular targets that may aid in the development of more effective pox-derived vaccines and antivirals.
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Affiliation(s)
- Mercedes Fernández-Escobar
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma, E-28029 Madrid, Spain
| | - Sara Baldanta
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma, E-28029 Madrid, Spain
| | - Hugh Reyburn
- Department of Immunology and Oncology, Centro Nacional de Biotecnología, Consejo Superior de Investigaciones Científicas (CSIC), Campus Universidad Autónoma, E-28049 Madrid, Spain
| | - Susana Guerra
- Department of Preventive Medicine, Public Health and Microbiology, Universidad Autónoma, E-28029 Madrid, Spain.
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16
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Leurent B, Reyburn H, Muro F, Mbakilwa H, Schellenberg D. Monitoring patient care through health facility exit interviews: an assessment of the Hawthorne effect in a trial of adherence to malaria treatment guidelines in Tanzania. BMC Infect Dis 2016; 16:59. [PMID: 26842751 PMCID: PMC4739341 DOI: 10.1186/s12879-016-1362-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 01/18/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Survey of patients exiting health facilities is a common way to assess consultation practices. It is, however, unclear to what extent health professionals may change their practices when they are aware of such interviews taking place, possibly paying more attention to following recommended practices. This so-called Hawthorne effect could have important consequences for interpreting research and programme monitoring, but has rarely been assessed. METHODS A three-arm cluster-randomised trial of interventions to improve adherence to guidelines for the use of anti-malarial drugs was conducted in Tanzania. Patient interviews were conducted outside health facilities on two randomly-selected days per week. Health workers also routinely documented consultations in their ledgers. The Hawthorne effect was investigated by comparing routine data according to whether exit interviews had been conducted on three key indicators of malaria care. Adjusted logistic mixed-effects models were used, taking into account the dependencies within health facilities and calendar days. RESULTS Routine data were collected on 19,579 consultations in 18 facilities. The odds of having a malaria rapid diagnostic test (RDT) result reported were 11 % higher on days when exit surveys were conducted (adjusted odds ratio 95 % CI: 0.98-1.26, p = 0.097), 17 % lower for prescribing an anti-malarial drug to patients with a negative RDT result (0.56-1.23, p = 0.343), and 27 % lower for prescribing an anti-malarial when no RDT result was reported (0.53-1.00, p = 0.052). The effect varied with time, with a U-shaped association over the study period (p < 0.001). We also observed a higher number of consultations recorded on days when exit-interviews were conducted (adjusted mean difference = 2.03, p < 0.001). CONCLUSIONS Although modest, there was some suggestion of better practice by health professionals on days when exit interviews were conducted. Researchers should be aware of the potential Hawthorne effect, and take into account assessment methods when generalising findings to the 'real word' setting. This effect is, however, likely to be context dependent, and further controlled evaluation across different settings should be conducted. TRIAL REGISTRATION ClinicalTrials.gov: NCT01292707 . Registered on 29th January 2011.
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Affiliation(s)
- Baptiste Leurent
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
| | - Hugh Reyburn
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | - Florida Muro
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Hilda Mbakilwa
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - David Schellenberg
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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17
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Hart PJ, O’Shaughnessy CM, Siggins MK, Bobat S, Kingsley RA, Goulding DA, Crump JA, Reyburn H, Micoli F, Dougan G, Cunningham AF, MacLennan CA. Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen. PLoS One 2016; 11:e0145945. [PMID: 26741681 PMCID: PMC4712142 DOI: 10.1371/journal.pone.0145945] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 12/10/2015] [Indexed: 01/08/2023] Open
Abstract
Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.
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Affiliation(s)
- Peter J. Hart
- School of Immunity and Infection, College of Medicine and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Colette M. O’Shaughnessy
- School of Immunity and Infection, College of Medicine and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Matthew K. Siggins
- School of Immunity and Infection, College of Medicine and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Saeeda Bobat
- School of Immunity and Infection, College of Medicine and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Robert A. Kingsley
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - David A. Goulding
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - John A. Crump
- Centre for International Health, University of Otago, Dunedin, New Zealand
- Kilimanjaro Christian Medical Centre and Kilimanjaro Christian Medical University College, Tumaini University, Moshi, Tanzania
- Division of Infectious Diseases and International Health, Duke University Medical Center, Durham, United States of America
- Duke Global Health Institute, Duke University, Durham, United States of America
| | - Hugh Reyburn
- London School of Hygiene and Tropical Medicine, Keppel Street, London, United Kingdom
| | - Francesca Micoli
- Sclavo-Behring Vaccines Institute for Global Health, a GlaxoSmithKline Company, Siena, Italy
| | - Gordon Dougan
- Centre for International Health, University of Otago, Dunedin, New Zealand
| | - Adam F. Cunningham
- School of Immunity and Infection, College of Medicine and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Calman A. MacLennan
- School of Immunity and Infection, College of Medicine and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
- Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- * E-mail:
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18
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Abstract
Objective In sub‐Saharan Africa, the use of malaria rapid diagnostic tests (mRDT) has raised awareness of alternative fever causes in children but few studies have included adults. To address this gap, we conducted a study of mRDT‐negative fever aetiologies among children and adults in Tanzania. Methods A total of 1028 patients aged 3 months to 50 years with a febrile illness and negative mRDT were enrolled from a Tanzanian hospital outpatient department. All had a physical examination and cultures from blood, nasopharynx/throat and urine. Patients were followed on Days 7 and 14 and children meeting WHO criteria for pneumonia were followed on Day 2 with chest radiology. Results Respiratory symptoms were the most frequent presenting complaint, reported by 20.3% of adults and 64.0% (339/530) of children. Of 38 X‐rayed children meeting WHO pneumonia criteria, 47.4% had a normal X‐ray. Overall, only 1.3% of 1028 blood cultures were positive. Salmonella typhi was the most prevalent pathogen isolated (7/13, 53.8%) and S. typhi patients reported fever for a median of 7 days (range 2–14). Children with bacteraemia did not present with WHO symptoms requiring antibiotic treatment. Young children and adults had similar prevalences of positive urine cultures (24/428 and 29/498, respectively). Conclusion Few outpatient fevers are caused by blood stream bacterial infection, and most adult bacteraemia would be identified by current clinical guidelines although paediatric bacteraemia may be more difficult to diagnose. While pneumonia may be overdiagnosed, urinary tract infection was relatively common. Our results emphasise the difficulty in identifying African children in need of antibiotics among the majority who do not.
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Affiliation(s)
- Helena Hildenwall
- Global Health - Health Systems and Policy, Karolinska Institutet, Stockholm, Sweden.,Joint Malaria Programme, St Augustine's Hospital, Muheza, Tanzania
| | - Ben Amos
- Joint Malaria Programme, St Augustine's Hospital, Muheza, Tanzania
| | - George Mtove
- Joint Malaria Programme, St Augustine's Hospital, Muheza, Tanzania.,National Institute for Medical Research, Amani Centre, Muheza, Tanga, Tanzania
| | - Florida Muro
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Kerstin Cederlund
- Department of Radiology, Karolinska University Hospital, Huddinge, Sweden.,Department of Clinical Science, Karolinska Institutet, Stockholm, Sweden
| | - Hugh Reyburn
- London School of Hygiene and Tropical Medicine, London, United Kingdom
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19
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Hutchinson E, Reyburn H, Hamlyn E, Long K, Meta J, Mbakilwa H, Chandler C. Bringing the state into the clinic? Incorporating the rapid diagnostic test for malaria into routine practice in Tanzanian primary healthcare facilities. Glob Public Health 2015; 12:1077-1091. [PMID: 26457440 PMCID: PMC5526135 DOI: 10.1080/17441692.2015.1091025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The roles that rapid, point-of-care tests will play in healthcare in low-income settings are likely to expand over the coming years. Yet, very little is known about how they are incorporated into practice, and what it means to use and rely upon them. This paper focuses on the rapid diagnostic test for malaria (mRDT), examining its introduction into low-level public health facilities in Tanzania within an intervention to improve the targeting of costly malaria medication. We interviewed 26 health workers to explore how a participatory training programme, mobile phone messages, posters and leaflets shaped the use and interpretation of the test. Drawing on notions of biopolitics, this paper examines how technologies of the self and mechanisms of surveillance bolstered the role mRDT in clinical decision-making. It shows how the significance of the test interacted with local knowledge, the availability of other medication, and local understandings of good clinical practice. Our findings suggest that in a context in which care is reduced to the provision of medicines, strict adherence to mRDT results may be underpinned by increasing the use of other pharmaceuticals or may leave health workers with patients for whom they are unable to provide care.
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Affiliation(s)
- Eleanor Hutchinson
- a Department of Global Health and Development , London School of Hygiene and Tropical Medicine , London , UK
| | - Hugh Reyburn
- b Department of Disease Control and Vector Biology , London School of Hygiene and Tropical Medicine , London , UK
| | - Eleanor Hamlyn
- a Department of Global Health and Development , London School of Hygiene and Tropical Medicine , London , UK
| | - Katie Long
- a Department of Global Health and Development , London School of Hygiene and Tropical Medicine , London , UK
| | - Judith Meta
- c Joint Malaria Programme , Kilimanjaro Christian Medical Centre , Moshi , Tanzania
| | - Hilda Mbakilwa
- c Joint Malaria Programme , Kilimanjaro Christian Medical Centre , Moshi , Tanzania
| | - Clare Chandler
- a Department of Global Health and Development , London School of Hygiene and Tropical Medicine , London , UK
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Manjurano A, Sepúlveda N, Nadjm B, Mtove G, Wangai H, Maxwell C, Olomi R, Reyburn H, Drakeley CJ, Riley EM, Clark TG. USP38, FREM3, SDC1, DDC, and LOC727982 Gene Polymorphisms and Differential Susceptibility to Severe Malaria in Tanzania. J Infect Dis 2015; 212:1129-39. [PMID: 25805752 PMCID: PMC4559194 DOI: 10.1093/infdis/jiv192] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 03/16/2015] [Indexed: 12/20/2022] Open
Abstract
Populations exposed to Plasmodium falciparum infection develop genetic mechanisms of protection against severe malarial disease. Despite decades of genetic epidemiological research, the sickle cell trait (HbAS) sickle cell polymorphism, ABO blood group, and other hemoglobinopathies remain the few major determinants in severe malaria to be replicated across different African populations and study designs. Within a case-control study in a region of high transmission in Tanzania (n = 983), we investigated the role of 40 new loci identified in recent genome-wide studies. In 32 loci passing quality control procedures, we found polymorphisms in USP38, FREM3, SDC1, DDC, and LOC727982 genes to be putatively associated with differential susceptibility to severe malaria. Established candidates explained 7.4% of variation in severe malaria risk (HbAS polymorphism, 6.3%; α-thalassemia, 0.3%; ABO group, 0.3%; and glucose-6-phosphate dehydrogenase deficiency, 0.5%) and the new polymorphisms, another 4.3%. The regions encompassing the loci identified are promising targets for the design of future treatment and control interventions.
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Affiliation(s)
- Alphaxard Manjurano
- Joint Malaria Programme,Kilimanjaro Christian Medical College, Moshi
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Nuno Sepúlveda
- Departments ofImmunology and Infection
- Centre of Statistics and Applications, University of Lisbon, Portugal
| | | | - George Mtove
- Joint Malaria Programme,Kilimanjaro Christian Medical College, Moshi
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Hannah Wangai
- Joint Malaria Programme,Kilimanjaro Christian Medical College, Moshi
| | - Caroline Maxwell
- Joint Malaria Programme,Kilimanjaro Christian Medical College, Moshi
| | - Raimos Olomi
- Joint Malaria Programme,Kilimanjaro Christian Medical College, Moshi
| | - Hugh Reyburn
- Joint Malaria Programme,Kilimanjaro Christian Medical College, Moshi
- Departments ofImmunology and Infection
| | - Christopher J. Drakeley
- Joint Malaria Programme,Kilimanjaro Christian Medical College, Moshi
- Departments ofImmunology and Infection
| | - Eleanor M. Riley
- Joint Malaria Programme,Kilimanjaro Christian Medical College, Moshi
- Departments ofImmunology and Infection
| | - Taane G. Clark
- Pathogen Molecular Biology
- Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, United Kingdom
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21
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Shelton JMG, Corran P, Risley P, Silva N, Hubbart C, Jeffreys A, Rowlands K, Craik R, Cornelius V, Hensmann M, Molloy S, Sepulveda N, Clark TG, Band G, Clarke GM, Spencer CCA, Kerasidou A, Campino S, Auburn S, Tall A, Ly AB, Mercereau-Puijalon O, Sakuntabhai A, Djimdé A, Maiga B, Touré O, Doumbo OK, Dolo A, Troye-Blomberg M, Mangano VD, Verra F, Modiano D, Bougouma E, Sirima SB, Ibrahim M, Hussain A, Eid N, Elzein A, Mohammed H, Elhassan A, Elhassan I, Williams TN, Ndila C, Macharia A, Marsh K, Manjurano A, Reyburn H, Lemnge M, Ishengoma D, Carter R, Karunaweera N, Fernando D, Dewasurendra R, Drakeley CJ, Riley EM, Kwiatkowski DP, Rockett KA. Genetic determinants of anti-malarial acquired immunity in a large multi-centre study. Malar J 2015; 14:333. [PMID: 26314886 PMCID: PMC4552443 DOI: 10.1186/s12936-015-0833-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 08/03/2015] [Indexed: 01/01/2023] Open
Abstract
Background Many studies report associations between human genetic factors and immunity to malaria but few have been reliably replicated. These studies are usually country-specific, use small sample sizes and are
not directly comparable due to differences in methodologies. This study brings together samples and data collected from multiple sites across Africa and Asia to use standardized methods to look for consistent genetic effects on anti-malarial antibody levels. Methods Sera, DNA samples and clinical data were collected from 13,299 individuals from ten sites in Senegal, Mali, Burkina Faso, Sudan, Kenya, Tanzania, and Sri Lanka using standardized methods. DNA was extracted and typed for 202 Single Nucleotide Polymorphisms with known associations to malaria or antibody production, and antibody levels to four clinical grade malarial antigens [AMA1, MSP1, MSP2, and (NANP)4] plus total IgE were measured by ELISA techniques. Regression models were used to investigate the associations of clinical and genetic factors with antibody levels. Results Malaria infection increased levels of antibodies to malaria antigens and, as expected, stable predictors of anti-malarial antibody levels included age, seasonality, location, and ethnicity. Correlations between antibodies to blood-stage antigens AMA1, MSP1 and MSP2 were higher between themselves than with antibodies to the (NANP)4 epitope of the pre-erythrocytic circumsporozoite protein, while there was little or no correlation with total IgE levels. Individuals with sickle cell trait had significantly lower antibody levels to all blood-stage antigens, and recessive homozygotes for CD36 (rs321198) had significantly lower anti-malarial antibody levels to MSP2. Conclusion Although the most significant finding with a consistent effect across sites was for sickle cell trait, its effect is likely to be via reducing a microscopically positive parasitaemia rather than directly on antibody levels. However, this study does demonstrate a framework for the feasibility of combining data from sites with heterogeneous malaria transmission levels across Africa and Asia with which to explore genetic effects on anti-malarial immunity. Electronic supplementary material The online version of this article (doi:10.1186/s12936-015-0833-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jennifer M G Shelton
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Patrick Corran
- London School of Hygiene and Tropical Medicine, Keppel Street, London, UK. .,National Institute for Biological Standards and Controls, South Mimms, Hertfordshire, UK.
| | - Paul Risley
- National Institute for Biological Standards and Controls, South Mimms, Hertfordshire, UK.
| | - Nilupa Silva
- National Institute for Biological Standards and Controls, South Mimms, Hertfordshire, UK.
| | - Christina Hubbart
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Anna Jeffreys
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Kate Rowlands
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Rachel Craik
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Victoria Cornelius
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Meike Hensmann
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Sile Molloy
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Nuno Sepulveda
- London School of Hygiene and Tropical Medicine, Keppel Street, London, UK.
| | - Taane G Clark
- London School of Hygiene and Tropical Medicine, Keppel Street, London, UK.
| | - Gavin Band
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Geraldine M Clarke
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Christopher C A Spencer
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Angeliki Kerasidou
- Nuffield Department of Population Health, The Ethox Centre, University of Oxford, Richard Doll Building, Old Road Campus, Oxford, OX3 7LF, UK.
| | - Susana Campino
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.
| | - Sarah Auburn
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK.
| | - Adama Tall
- Infectious Diseases Epidemiology Unit, Institut Pasteur, BP 220, Dakar, Senegal.
| | - Alioune Badara Ly
- Infectious Diseases Epidemiology Unit, Institut Pasteur, BP 220, Dakar, Senegal.
| | - Odile Mercereau-Puijalon
- Parasite Molecular Immunology Unit, Institut Pasteur, 28 rue du Docteur Roux, 75724, Paris Cedex 15, France.
| | - Anavaj Sakuntabhai
- Unité de Génétique Fonctionnelle des Maladies Infectieuses, Institut Pasteur, 28 rue du Docteur Roux, 75724, Paris Cedex 15, France. .,Centre National de la Recherche Scientifique, URA3012, 28 rue du Docteur Roux, 75724, Paris Cedex 15, France.
| | - Abdoulaye Djimdé
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Odonto-Stomatology, Malaria Research and Training Center, USTTB, BP 1805, Bamako, Mali.
| | - Boubacar Maiga
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Odonto-Stomatology, Malaria Research and Training Center, USTTB, BP 1805, Bamako, Mali.
| | - Ousmane Touré
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Odonto-Stomatology, Malaria Research and Training Center, USTTB, BP 1805, Bamako, Mali.
| | - Ogobara K Doumbo
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Odonto-Stomatology, Malaria Research and Training Center, USTTB, BP 1805, Bamako, Mali.
| | - Amagana Dolo
- Department of Epidemiology of Parasitic Diseases, Faculty of Medicine, Pharmacy and Odonto-Stomatology, Malaria Research and Training Center, USTTB, BP 1805, Bamako, Mali.
| | - Marita Troye-Blomberg
- Department of Molecular Biosciences, Wenner-Gren Institute, Stockholm University, Svante Arrheniusväg 20B, 106 91, Stockholm, Sweden.
| | - Valentina D Mangano
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - Frederica Verra
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - David Modiano
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185, Rome, Italy.
| | - Edith Bougouma
- Centre de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso.
| | - Sodiomon B Sirima
- Centre de Recherche et de Formation sur le Paludisme, Ouagadougou, Burkina Faso.
| | - Muntaser Ibrahim
- Institute of Endemic Diseases, University of Khartoum, Medical Sciences Campus, Qasser Street, Khartoum, Sudan.
| | - Ayman Hussain
- Institute of Endemic Diseases, University of Khartoum, Medical Sciences Campus, Qasser Street, Khartoum, Sudan.
| | - Nahid Eid
- Institute of Endemic Diseases, University of Khartoum, Medical Sciences Campus, Qasser Street, Khartoum, Sudan.
| | - Abier Elzein
- Institute of Endemic Diseases, University of Khartoum, Medical Sciences Campus, Qasser Street, Khartoum, Sudan.
| | - Hiba Mohammed
- Institute of Endemic Diseases, University of Khartoum, Medical Sciences Campus, Qasser Street, Khartoum, Sudan.
| | - Ahmed Elhassan
- Institute of Endemic Diseases, University of Khartoum, Medical Sciences Campus, Qasser Street, Khartoum, Sudan.
| | - Ibrahim Elhassan
- Institute of Endemic Diseases, University of Khartoum, Medical Sciences Campus, Qasser Street, Khartoum, Sudan.
| | - Thomas N Williams
- KEMRI-Wellcome Trust Research Programme, CGMRC, PO Box 230-80108, Kilifi, Kenya. .,Department of Medicine, Imperial College, St Mary's Campus, Norfolk Place, London, W2 1PG, UK.
| | - Carolyne Ndila
- KEMRI-Wellcome Trust Research Programme, CGMRC, PO Box 230-80108, Kilifi, Kenya.
| | - Alexander Macharia
- KEMRI-Wellcome Trust Research Programme, CGMRC, PO Box 230-80108, Kilifi, Kenya.
| | - Kevin Marsh
- KEMRI-Wellcome Trust Research Programme, CGMRC, PO Box 230-80108, Kilifi, Kenya.
| | - Alphaxard Manjurano
- London School of Hygiene and Tropical Medicine, Keppel Street, London, UK. .,Kilimanjaro Christian Medical College, Tumaini University, Moshi, Tanzania.
| | - Hugh Reyburn
- London School of Hygiene and Tropical Medicine, Keppel Street, London, UK. .,Kilimanjaro Christian Medical College, Tumaini University, Moshi, Tanzania.
| | - Martha Lemnge
- National Institute for Medical Research, Ocean Road, Dar es Salaam, Tanzania.
| | - Deus Ishengoma
- National Institute for Medical Research, Ocean Road, Dar es Salaam, Tanzania.
| | - Richard Carter
- Division of Biological Sciences, Ashworth Laboratories, University of Edinburgh, West Mains Rd., Edinburgh, EH9 3JT, UK.
| | - Nadira Karunaweera
- Department of Parasitology, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo, Sri Lanka.
| | - Deepika Fernando
- Department of Parasitology, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo, Sri Lanka.
| | - Rajika Dewasurendra
- Department of Parasitology, Faculty of Medicine, University of Colombo, Kynsey Road, Colombo, Sri Lanka.
| | - Christopher J Drakeley
- London School of Hygiene and Tropical Medicine, Keppel Street, London, UK. .,Kilimanjaro Christian Medical College, Tumaini University, Moshi, Tanzania.
| | - Eleanor M Riley
- London School of Hygiene and Tropical Medicine, Keppel Street, London, UK. .,Kilimanjaro Christian Medical College, Tumaini University, Moshi, Tanzania.
| | - Dominic P Kwiatkowski
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK. .,Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.
| | - Kirk A Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford, UK. .,Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, CB10 1SA, UK.
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Prasad N, Murdoch DR, Reyburn H, Crump JA. Etiology of Severe Febrile Illness in Low- and Middle-Income Countries: A Systematic Review. PLoS One 2015; 10:e0127962. [PMID: 26126200 PMCID: PMC4488327 DOI: 10.1371/journal.pone.0127962] [Citation(s) in RCA: 101] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 04/22/2015] [Indexed: 02/04/2023] Open
Abstract
Background With apparent declines in malaria worldwide during the last decade and more widespread use of malaria rapid diagnostic tests, healthcare workers in low-resource areas face a growing proportion of febrile patients without malaria. We sought to describe current knowledge and identify information gaps of the etiology severe febrile illness in low-and middle-income countries. Methods and Findings We conducted a systematic review of studies conducted in low-and-middle income countries 1980–2013 that prospectively assessed consecutive febrile patients admitted to hospital using rigorous laboratory-based case definitions. We found 45 eligible studies describing 54,578 patients; 9,771 (17.9%) had a positive result for ≥1 pathogen meeting diagnostic criteria. There were no eligible studies identified from Southern and Middle Africa, Eastern Asia, Oceania, Latin American and Caribbean regions, and the European region. The median (range) number of diagnostic tests meeting our confirmed laboratory case definitions was 2 (1 to 11) per study. Of diagnostic tests, 5,052 (10.3%) of 49,143 had confirmed bacterial or fungal bloodstream infection; 709 (3.8%) of 18,142 had bacterial zoonosis; 3,488 (28.5%) of 12,245 had malaria; and 1,804 (17.4%) of 10,389 had a viral infection. Conclusions We demonstrate a wide range of pathogens associated with severe febrile illness and highlight the substantial information gaps regarding the geographic distribution and role of common pathogens. High quality severe febrile illness etiology research that is comprehensive with respect to pathogens and geographically representative is needed.
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Affiliation(s)
- Namrata Prasad
- Centre for International Health, Dunedin School of Medicine, University of Otago, PO Box 56, Dunedin, 9054, New Zealand
| | - David R. Murdoch
- Department of Pathology, University of Otago Christchurch, 2 Riccarton Avenue, PO Box 4345, Christchurch, 8011, New Zealand
| | - Hugh Reyburn
- Department of Disease Control, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, United Kingdom
| | - John A. Crump
- Centre for International Health, Dunedin School of Medicine, University of Otago, PO Box 56, Dunedin, 9054, New Zealand
- * E-mail:
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Muro F, Reyburn R, Reyburn H. Acute respiratory infection and bacteraemia as causes of non-malarial febrile illness in African children: a narrative review. Pneumonia (Nathan) 2015; 6:6-17. [PMID: 26594615 PMCID: PMC4650196 DOI: 10.15172/pneu.2015.6/488] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 03/13/2015] [Indexed: 12/16/2022] Open
Abstract
The replacement of "presumptive treatment for malaria" by "test before treat" strategies for the management of febrile illness is raising awareness of the importance of knowing more about the causes of illness in children who are suspected to have malaria but return a negative parasitological test. The most common cause of non-malarial febrile illness (NMFI) in African children is respiratory tract infection. Whilst the bacterial causes of NMFI are well known, the increasing use of sensitive techniques such as polymerase chain reaction (PCR) tests is revealing large numbers of viruses that are potential respiratory pathogens. However, many of these organisms are commonly present in the respiratory tract of healthy children so causality and risk factors for pneumonia remain poorly understood. Infection with a combination of viral and bacterial pathogens is increasingly recognised as important in the pathogenesis of pneumonia. Similarly, blood stream infections with organisms typically grown by aerobic culture are well known but a growing number of organisms that can be identified only by PCR, viral culture, or serology are now recognised to be common pathogens in African children. The high mortality of hospitalised children on the first or second day of admission suggests that, unless results are rapidly available, diagnostic tests to identify specific causes of illness will still be of limited use in guiding the potentially life saving decisions relating to initial treatment of children admitted to district hospitals in Africa with severe febrile illness and a negative test for malaria. Malaria control and the introduction of vaccines against Haemophilus influenzae type b and pneumococcal disease are contributing to improved child survival in Africa. However, increased parasitological testing for malaria is associated with increased use of antibiotics to which resistance is already high.
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Affiliation(s)
- Florid Muro
- Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Rita Reyburn
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Parkville, Victoria Australia
- New Vaccine Evaluation Project, Colonial War Memorial Hospital, Suva, Fiji
| | - Hugh Reyburn
- Department of Disease Control, London School of Hygiene and Tropical Medicine, Keppel St London, WICE7HT UK
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Cundill B, Mbakilwa H, Chandler CI, Mtove G, Mtei F, Willetts A, Foster E, Muro F, Mwinyishehe R, Mandike R, Olomi R, Whitty CJ, Reyburn H. Prescriber and patient-oriented behavioural interventions to improve use of malaria rapid diagnostic tests in Tanzania: facility-based cluster randomised trial. BMC Med 2015; 13:118. [PMID: 25980737 PMCID: PMC4445498 DOI: 10.1186/s12916-015-0346-z] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 04/13/2015] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The increasing investment in malaria rapid diagnostic tests (RDTs) to differentiate malarial and non-malarial fevers, and an awareness of the need to improve case management of non-malarial fever, indicates an urgent need for high quality evidence on how best to improve prescribers' practices. METHODS A three-arm stratified cluster-randomised trial was conducted in 36 primary healthcare facilities from September 2010 to March 2012 within two rural districts in northeast Tanzania where malaria transmission has been declining. Interventions were guided by formative mixed-methods research and were introduced in phases. Prescribing staff from all facilities received standard Ministry of Health RDT training. Prescribers from facilities in the health worker (HW) and health worker-patient (HWP) arms further participated in small interactive peer-group training sessions with the HWP additionally receiving clinic posters and patient leaflets. Performance feedback and motivational mobile-phone text messaging (SMS) were added to the HW and HWP arms in later phases. The primary outcome was the proportion of patients with a non-severe, non-malarial illness incorrectly prescribed a (recommended) antimalarial. Secondary outcomes investigated RDT uptake, adherence to results, and antibiotic prescribing. RESULTS Standard RDT training reduced pre-trial levels of antimalarial prescribing, which was sustained throughout the trial. Both interventions significantly lowered incorrect prescribing of recommended antimalarials from 8% (749/8,942) in the standard training arm to 2% (250/10,118) in the HW arm (adjusted RD (aRD) 4%; 95% confidence interval (CI) 1% to 6%; P = 0.008) and 2% (184/10,163) in the HWP arm (aRD 4%; 95% CI 1% to 6%; P = 0.005). Small group training and SMS were incrementally effective. There was also a significant reduction in the prescribing of antimalarials to RDT-negatives but no effect on RDT-positives receiving an ACT. Antibiotic prescribing was significantly lower in the HWP arm but had increased in all arms compared with pre-trial levels. CONCLUSIONS Small group training with SMS was associated with an incremental and sustained improvement in prescriber adherence to RDT results and reducing over-prescribing of antimalarials to close to zero. These interventions may become increasingly important to cope with the wider range of diagnostic and treatment options for patients with acute febrile illness in Africa.
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Affiliation(s)
- Bonnie Cundill
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, Keppel St, London, WCIE 7HT, UK.
| | - Hilda Mbakilwa
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Box 2228, Moshi, Tanzania.
| | - Clare Ir Chandler
- Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, Keppel St, London, WCIE 7HT, UK.
| | - George Mtove
- National Institute for Medical Research, Amani Centre, Tanga, Tanzania.
| | - Frank Mtei
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Box 2228, Moshi, Tanzania.
| | - Annie Willetts
- Wellsense International Public Health Consultants, P.O. Box 788, Kilifi, Kenya.
| | - Emily Foster
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Box 2228, Moshi, Tanzania.
| | - Florida Muro
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Box 2228, Moshi, Tanzania.
| | - Rahim Mwinyishehe
- National Institute for Medical Research, Amani Centre, Tanga, Tanzania.
| | - Renata Mandike
- National Malaria Control Programme, Ministry of Health and Social Welfare, Ocean Road, Dar es Salaam, Tanzania.
| | - Raimos Olomi
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Box 2228, Moshi, Tanzania.
| | - Christopher Jm Whitty
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, WCIE 7HT, UK.
| | - Hugh Reyburn
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel St, London, WCIE 7HT, UK.
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25
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Muro F, Mtove G, Mosha N, Wangai H, Harrison N, Hildenwall H, Schellenberg D, Todd J, Olomi R, Reyburn H. Effect of context on respiratory rate measurement in identifying non-severe pneumonia in African children. Trop Med Int Health 2015; 20:757-65. [PMID: 25728867 PMCID: PMC4642338 DOI: 10.1111/tmi.12492] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Objective Cough or difficult breathing and an increased respiratory rate for their age are the commonest indications for outpatient antibiotic treatment in African children. We aimed to determine whether respiratory rate was likely to be transiently raised by a number of contextual factors in a busy clinic leading to inaccurate diagnosis. Methods Respiratory rates were recorded in children aged 2–59 months presenting with cough or difficulty breathing to one of the two busy outpatient clinics and then repeated at 10‐min intervals over 1 h in a quiet setting. Results One hundred and sixty‐seven children were enrolled with a mean age of 7.1 (SD ± 2.9) months in infants and 27.6 (SD ± 12.8) months in children aged 12–59 months. The mean respiratory rate declined from 42.3 and 33.6 breaths per minute (bpm) in the clinic to 39.1 and 32.6 bpm after 10 min in a quiet room and to 39.2 and 30.7 bpm (P < 0.001) after 60 min in younger and older children, respectively. This resulted in 11/13 (85%) infants and 2/15 (13%) older children being misclassified with non‐severe pneumonia. In a random effects linear regression model, the variability in respiratory rate within children (42%) was almost as much as the variability between children (58%). Changing the respiratory rates cut‐offs to higher thresholds resulted in a small reduction in the proportion of non‐severe pneumonia mis‐classifications in infants. Conclusion Noise and other contextual factors may cause a transient increase in respiratory rate and consequently misclassification of non‐severe pneumonia. However, this effect is less pronounced in older children than infants. Respiratory rate is a difficult sign to measure as the variation is large between and within children. More studies of the accuracy and utility of respiratory rate as a proxy for non‐severe pneumonia diagnosis in a busy clinic are needed.
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Affiliation(s)
- Florida Muro
- Kilimanjaro Christian Medical University College, Moshi, Tanzania
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26
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Griffin JT, Hollingsworth TD, Reyburn H, Drakeley CJ, Riley EM, Ghani AC. Gradual acquisition of immunity to severe malaria with increasing exposure. Proc Biol Sci 2015; 282:20142657. [PMID: 25567652 PMCID: PMC4309004 DOI: 10.1098/rspb.2014.2657] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 12/04/2014] [Indexed: 11/12/2022] Open
Abstract
Previous analyses have suggested that immunity to non-cerebral severe malaria due to Plasmodium falciparum is acquired after only a few infections, whereas longitudinal studies show that some children experience multiple episodes of severe disease, suggesting that immunity may not be acquired so quickly. We fitted a mathematical model for the acquisition and loss of immunity to severe disease to the age distribution of severe malaria cases stratified by symptoms from a range of transmission settings in Tanzania, combined with data from several African countries on the age distribution and overall incidence of severe malaria. We found that immunity to severe disease was acquired more gradually with exposure than previously thought. The model also suggests that physiological changes, rather than exposure, may alter the symptoms of disease with increasing age, suggesting that a later age at infection would be associated with a higher proportion of cases presenting with cerebral malaria regardless of exposure. This has consequences for the expected pattern of severe disease as transmission changes. Careful monitoring of the decline in immunity associated with reduced transmission will therefore be needed to ensure rebound epidemics of severe and fatal malaria are avoided.
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Affiliation(s)
- Jamie T Griffin
- MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College London, London W2 1PG, UK
| | - T Déirdre Hollingsworth
- Mathematics Institute, University of Warwick, Coventry CV4 7AL, UK School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK Department of Clinical Sciences, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L3 5QA, UK
| | - Hugh Reyburn
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Chris J Drakeley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Eleanor M Riley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Azra C Ghani
- MRC Centre for Outbreak Analysis and Modelling, Department of Infectious Disease Epidemiology, Faculty of Medicine, Imperial College London, London W2 1PG, UK
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Manjurano A, Sepulveda N, Nadjm B, Mtove G, Wangai H, Maxwell C, Olomi R, Reyburn H, Riley EM, Drakeley CJ, Clark TG. African glucose-6-phosphate dehydrogenase alleles associated with protection from severe malaria in heterozygous females in Tanzania. PLoS Genet 2015; 11:e1004960. [PMID: 25671784 PMCID: PMC4335500 DOI: 10.1371/journal.pgen.1004960] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 12/17/2014] [Indexed: 11/24/2022] Open
Abstract
X-linked Glucose-6-phosphate dehydrogenase (G6PD) A- deficiency is prevalent in sub-Saharan Africa populations, and has been associated with protection from severe malaria. Whether females and/or males are protected by G6PD deficiency is uncertain, due in part to G6PD and malaria phenotypic complexity and misclassification. Almost all large association studies have genotyped a limited number of G6PD SNPs (e.g. G6PD202 / G6PD376), and this approach has been too blunt to capture the complete epidemiological picture. Here we have identified 68 G6PD polymorphisms and analysed 29 of these (i.e. those with a minor allele frequency greater than 1%) in 983 severe malaria cases and controls in Tanzania. We establish, across a number of SNPs including G6PD376, that only female heterozygotes are protected from severe malaria. Haplotype analysis reveals the G6PD locus to be under balancing selection, suggesting a mechanism of protection relying on alleles at modest frequency and avoiding fixation, where protection provided by G6PD deficiency against severe malaria is offset by increased risk of life-threatening complications. Our study also demonstrates that the much-needed large-scale studies of severe malaria and G6PD enzymatic function across African populations require the identification and analysis of the full repertoire of G6PD genetic markers. Glucose-6-phosphate dehydrogenase (G6PD) is an essential enzyme that protects red blood cells from oxidative damage. Numerous genetic variants of G6PD, residing in the X chromosome, are found among African populations: mutations causing A- deficiency can lead to serious clinical outcomes (including hemolytic anemia) but also confer protection against severe malaria. Epidemiological studies have used some of the genetic markers that cause A- deficiency to establish who is protected from severe malaria, with differing results. Whether females, with one or two copies of mutant genes, males with one copy, or both genders are protected is uncertain. This uncertainty is due to G6PD and malaria phenotypic complexity and misclassification, and to genetic differences between populations and the limited numbers of genetic markers (usually 2) considered. In this study we analysed more than 30 G6PD genetic markers in 506 Tanzanian children with severe malaria and 477 without malaria. We found that only females with one normal and one mutant copy of the gene (heterozygotes) were protected from severe malaria. Further, we established that the G6PD gene is under evolutionary pressure with the likely mechanism being selection by malaria. Our work demonstrates that studies of severe malaria and G6PD enzymatic function across African populations require, in addition to complete and accurate G6PD phenotypic classification, the identification and analysis of the full repertoire of G6PD genetic markers.
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Affiliation(s)
- Alphaxard Manjurano
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Nuno Sepulveda
- Department of Infection and Immunology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Behzad Nadjm
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - George Mtove
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Hannah Wangai
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Caroline Maxwell
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Raimos Olomi
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
| | - Hugh Reyburn
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
- Department of Infection and Immunology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Eleanor M. Riley
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
- Department of Infection and Immunology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Christopher J. Drakeley
- Joint Malaria Programme, Kilimanjaro Christian Medical College, Moshi, Tanzania
- Department of Infection and Immunology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Taane G. Clark
- Pathogen Molecular Biology Department, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
- * E-mail:
| | - MalariaGEN Consortium
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
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Kiguli S, Maitland K, George EC, Olupot-Olupot P, Opoka RO, Engoru C, Akech SO, Nyeko R, Mtove G, Reyburn H, Levin M, Babiker AG, Gibb DM, Crawley J. Anaemia and blood transfusion in African children presenting to hospital with severe febrile illness. BMC Med 2015; 13:21. [PMID: 25640706 PMCID: PMC4313469 DOI: 10.1186/s12916-014-0246-7] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 12/08/2014] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Severe anaemia in children is a leading cause of hospital admission and a major cause of mortality in sub-Saharan Africa, yet there are limited published data on blood transfusion in this vulnerable group. METHODS We present data from a large controlled trial of fluid resuscitation (Fluid Expansion As Supportive Therapy (FEAST) trial) on the prevalence, clinical features, and transfusion management of anaemia in children presenting to hospitals in three East African countries with serious febrile illness (predominantly malaria and/or sepsis) and impaired peripheral perfusion. RESULTS Of 3,170 children in the FEAST trial, 3,082 (97%) had baseline haemoglobin (Hb) measurement, 2,346/3,082 (76%) were anaemic (Hb <10 g/dL), and 33% severely anaemic (Hb <5 g/dL). Prevalence of severe anaemia varied from 12% in Kenya to 41% in eastern Uganda. 1,387/3,082 (45%) children were transfused (81% within 8 hours). Adherence to WHO transfusion guidelines was poor. Among severely anaemic children who were not transfused, 52% (54/103) died within 8 hours, and 90% of these deaths occurred within 2.5 hours of randomisation. By 24 hours, 128/1,002 (13%) severely anaemic children had died, compared to 36/501 (7%) and 71/843 (8%) of those with moderate and mild anaemia, respectively. Among children without severe hypotension who were randomised to receive fluid boluses of 0.9% saline or albumin, mortality was increased (10.6% and 10.5%, respectively) compared to controls (7.2%), regardless of admission Hb level. Repeat transfusion varied from ≤2% in Kenya/Tanzania to 6 to 13% at the four Ugandan centres. Adverse reactions to blood were rare (0.4%). CONCLUSIONS Severe anaemia complicates one third of childhood admissions with serious febrile illness to hospitals in East Africa, and is associated with increased mortality. A high proportion of deaths occurred within 2.5 hours of admission, emphasizing the need for rapid recognition and prompt blood transfusion. Adherence to current WHO transfusion guidelines was poor. The high rates of re-transfusion suggest that 20 mL/kg whole blood or 10 mL/kg packed cells may undertreat a significant proportion of anaemic children. Future evaluation of the impact of a larger volume of transfused blood and optimum transfusion management of children with Hb of <6 g/dL is warranted.
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Affiliation(s)
| | - Kathryn Maitland
- Kilifi Clinical Trials Facility, KEMRI-Wellcome Trust Research Programme, Nairobi, Kenya.
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Chandler CIR, Meta J, Ponzo C, Nasuwa F, Kessy J, Mbakilwa H, Haaland A, Reyburn H. The development of effective behaviour change interventions to support the use of malaria rapid diagnostic tests by Tanzanian clinicians. Implement Sci 2014; 9:83. [PMID: 24969367 PMCID: PMC4227094 DOI: 10.1186/1748-5908-9-83] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 06/09/2014] [Indexed: 12/30/2022] Open
Abstract
Background Parasitological confirmation is now recommended for all cases of suspected malaria. The roll-out of rapid diagnostic tests (RDTs) is hoped to enable this goal in low resource settings through point of care testing. However, simply making RDTs available has not led to high uptake of the tests or adherence to results by clinicians, with malaria continuing to be overdiagnosed in many settings. We undertook to design an evidence-based intervention package that would be sufficient to support the introduction of RDTs at dispensaries in Tanzania, to be evaluated through the Targeting Artemisinin Combination Therapy (TACT) cluster randomised controlled trial. Methods We describe five steps in our intervention design: formative research, review of existing evidence and theory, a workshop to define the intervention approach and content and results of formative research, engagement with behaviour change theory and literature, detailed design of intervention materials and piloting and pretesting of intervention materials. This involved fieldwork with a total of 19 health workers and 212 community members in northeast Tanzania. Results The formative research suggested that RDTs were a potential source of conflict in the health worker-patient interaction, but that health workers used various techniques to resolve this, including provision of antimalarial drugs for RDT-negative patients. Our reviews showed that evidence was mixed regarding the effectiveness of different methods and theories to support change in prescribing practice. Our design process is presented, drawing from this collective evidence. We describe the final TACT intervention package (including interactive small group workshops, feedback text messages, motivational text messages and patient information leaflets and posters) in terms of its programme theory and implementation theory. Conclusions Our study suggests that evidence-based design of complex interventions is possible. The use of formative research to understand malaria overdiagnosis in context was central to the design of the intervention as well as empirical research to test materials and methods prior to implementation. The TACT interventions may be appropriate for other settings where clinicians face similar challenges with malaria diagnostics. Trial registration NCT01292707.
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Affiliation(s)
- Clare I R Chandler
- Department of Global Health and Development, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK.
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Reynolds J, DiLiberto D, Mangham-Jefferies L, Ansah EK, Lal S, Mbakilwa H, Bruxvoort K, Webster J, Vestergaard LS, Yeung S, Leslie T, Hutchinson E, Reyburn H, Lalloo DG, Schellenberg D, Cundill B, Staedke SG, Wiseman V, Goodman C, Chandler CIR. The practice of 'doing' evaluation: lessons learned from nine complex intervention trials in action. Implement Sci 2014; 9:75. [PMID: 24935096 PMCID: PMC4079170 DOI: 10.1186/1748-5908-9-75] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 06/13/2014] [Indexed: 01/16/2023] Open
Abstract
Background There is increasing recognition among trialists of the challenges in understanding how particular ‘real-life’ contexts influence the delivery and receipt of complex health interventions. Evaluations of interventions to change health worker and/or patient behaviours in health service settings exemplify these challenges. When interpreting evaluation data, deviation from intended intervention implementation is accounted for through process evaluations of fidelity, reach, and intensity. However, no such systematic approach has been proposed to account for the way evaluation activities may deviate in practice from assumptions made when data are interpreted. Methods A collective case study was conducted to explore experiences of undertaking evaluation activities in the real-life contexts of nine complex intervention trials seeking to improve appropriate diagnosis and treatment of malaria in varied health service settings. Multiple sources of data were used, including in-depth interviews with investigators, participant-observation of studies, and rounds of discussion and reflection. Results and discussion From our experiences of the realities of conducting these evaluations, we identified six key ‘lessons learned’ about ways to become aware of and manage aspects of the fabric of trials involving the interface of researchers, fieldworkers, participants and data collection tools that may affect the intended production of data and interpretation of findings. These lessons included: foster a shared understanding across the study team of how individual practices contribute to the study goals; promote and facilitate within-team communications for ongoing reflection on the progress of the evaluation; establish processes for ongoing collaboration and dialogue between sub-study teams; the importance of a field research coordinator bridging everyday project management with scientific oversight; collect and review reflective field notes on the progress of the evaluation to aid interpretation of outcomes; and these approaches should help the identification of and reflection on possible overlaps between the evaluation and intervention. Conclusion The lessons we have drawn point to the principle of reflexivity that, we argue, needs to become part of standard practice in the conduct of evaluations of complex interventions to promote more meaningful interpretations of the effects of an intervention and to better inform future implementation and decision-making.
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Affiliation(s)
- Joanna Reynolds
- Department of Social and Environmental Health Research, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK.
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Manongi R, Mtei F, Mtove G, Nadjm B, Muro F, Alegana V, Noor AM, Todd J, Reyburn H. Inpatient child mortality by travel time to hospital in a rural area of Tanzania. Trop Med Int Health 2014; 19:555-62. [PMID: 24661618 PMCID: PMC4269975 DOI: 10.1111/tmi.12294] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To investigate the association, if any, between child mortality and distance to the nearest hospital. METHODS The study was based on data from a 1-year study of the cause of illness in febrile paediatric admissions to a district hospital in north-east Tanzania. All villages in the catchment population were geolocated, and travel times were estimated from availability of local transport. Using bands of travel time to hospital, we compared admission rates, inpatient case fatality rates and child mortality rates in the catchment population using inpatient deaths as the numerator. RESULTS Three thousand hundred and eleven children under the age of 5 years were included of whom 4.6% died; 2307 were admitted from <3 h away of whom 3.4% died and 804 were admitted from ≥3 h away of whom 8.0% died. The admission rate declined from 125/1000 catchment population at <3 h away to 25/1000 at ≥3 h away, and the corresponding hospital deaths/catchment population were 4.3/1000 and 2.0/1000, respectively. Children admitted from more than 3 h away were more likely to be male, had a longer pre-admission duration of illness and a shorter time between admission and death. Assuming uniform mortality in the catchment population, the predicted number of deaths not benefiting from hospital admission prior to death increased by 21.4% per hour of travel time to hospital. If the same admission and death rates that were found at <3 h from the hospital applied to the whole catchment population and if hospital care conferred a 30% survival benefit compared to home care, then 10.3% of childhood deaths due to febrile illness in the catchment population would have been averted. CONCLUSIONS The mortality impact of poor access to hospital care in areas of high paediatric mortality is likely to be substantial although uncertainty over the mortality benefit of inpatient care is the largest constraint in making an accurate estimate.
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Meta J, Nasuwa F, Mwendo E, Reyburn H, Bower JH. Improving the consent process for neuroepidemiologic research in resource-poor settings. Neurology 2014; 82:895-7. [PMID: 24616193 DOI: 10.1212/wnl.0000000000000184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Judith Meta
- From the Joint Malaria Programme (J.M., F.N., H.R.), London School of Hygiene and Tropical Medicine; Kilimanjaro Christian Medical University College (E.M.), Moshi, Tanzania; and the Department of Neurology (J.H.B.), Mayo Clinic, Rochester, MN
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Kiguli S, Akech SO, Mtove G, Opoka RO, Engoru C, Olupot-Olupot P, Nyeko R, Evans J, Crawley J, Prevatt N, Reyburn H, Levin M, George EC, South A, Babiker AG, Gibb DM, Maitland K. Authors' reply to Southall. BMJ 2014; 348:g1619. [PMID: 24554466 DOI: 10.1136/bmj.g1619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Sarah Kiguli
- Department of Paediatrics, Mulago Hospital, Makerere University, Kampala, Uganda
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Kiguli S, Akech SO, Mtove G, Opoka RO, Engoru C, Olupot-Olupot P, Nyeko R, Evans J, Crawley J, Prevatt N, Reyburn H, Levin M, George EC, South A, Babiker AG, Gibb DM, Maitland K. WHO guidelines on fluid resuscitation in children: missing the FEAST data. BMJ 2014; 348:f7003. [PMID: 24423891 PMCID: PMC5693317 DOI: 10.1136/bmj.f7003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Sarah Kiguli
- Department of Paediatrics, Mulago Hospital, Makerere University, Kampala, Uganda
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Biggs HM, Lester R, Nadjm B, Mtove G, Todd JE, Kinabo GD, Philemon R, Amos B, Morrissey AB, Reyburn H, Crump JA. Invasive Salmonella infections in areas of high and low malaria transmission intensity in Tanzania. Clin Infect Dis 2013; 58:638-47. [PMID: 24336909 DOI: 10.1093/cid/cit798] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The epidemiology of Salmonella Typhi and invasive nontyphoidal Salmonella (NTS) differs, and prevalence of these pathogens among children in sub-Saharan Africa may vary in relation to malaria transmission intensity. METHODS We compared the prevalence of bacteremia among febrile pediatric inpatients aged 2 months to 13 years recruited at sites of high and low malaria endemicity in Tanzania. Enrollment at Teule Hospital, the high malaria transmission site, was from June 2006 through May 2007, and at Kilimanjaro Christian Medical Centre (KCMC), the low malaria transmission site, from September 2007 through August 2008. Automated blood culture, malaria microscopy with Giemsa-stained blood films, and human immunodeficiency virus testing were performed. RESULTS At Teule, 3639 children were enrolled compared to 467 at KCMC. Smear-positive malaria was detected in 2195 of 3639 (60.3%) children at Teule and 11 of 460 (2.4%) at KCMC (P < .001). Bacteremia was present in 336 of 3639 (9.2%) children at Teule and 20 of 463 (4.3%) at KCMC (P < .001). NTS was isolated in 162 of 3639 (4.5%) children at Teule and 1 of 463 (0.2%) at KCMC (P < .001). Salmonella Typhi was isolated from 11 (0.3%) children at Teule and 6 (1.3%) at KCMC (P = .008). With NTS excluded, the prevalence of bacteremia at Teule was 5.0% and at KCMC 4.1% (P = .391). CONCLUSIONS Where malaria transmission was intense, invasive NTS was common and Salmonella Typhi was uncommon, whereas the inverse was observed at a low malaria transmission site. The relationship between these pathogens, the environment, and the host is a compelling area for further research.
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Affiliation(s)
- Holly M Biggs
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, North Carolina
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Mohammed A, Ndaro A, Kalinga A, Manjurano A, Mosha JF, Mosha DF, van Zwetselaar M, Koenderink JB, Mosha FW, Alifrangis M, Reyburn H, Roper C, Kavishe RA. Trends in chloroquine resistance marker, Pfcrt-K76T mutation ten years after chloroquine withdrawal in Tanzania. Malar J 2013; 12:415. [PMID: 24225406 PMCID: PMC3830541 DOI: 10.1186/1475-2875-12-415] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 11/11/2013] [Indexed: 12/22/2022] Open
Abstract
Background Plasmodium falciparum resistance to anti-malarial drugs remains a major obstacle to the control of malaria. In 2001 Tanzania replaced chloroquine (CQ) with sulphadoxine-pyrimethamine (SP) as first-line drug, which in turn was replaced by artemisinin combination therapy in 2006. SP has however, continued to be used in intermittent preventive treatment of malaria in pregnancy (IPTp) despite reports of high levels of resistance to SP due to the lack of alternatives to SP for IPTp. Recent reports have indicated recovery of CQ-susceptibility in Malawi, Kenya, Mozambique, and Tanzania based on the prevalence of wild types at codon 76 of the Pfcrt gene in indigenous P. falciparum populations. The current prevalence of this Pfcrt-76 CQ resistance marker from six regions of Tanzania mainland is hereby reported. Methods DNA extracted from filter-paper dried blood spots and rapid diagnostics kit strips collected from finger-prick blood were used to genotype the Pfcrt-76 resistance marker using PCR-RFLP. Data from previously published studies were used to generate CQ susceptibility recovery trends using logistic regression model. Results Seven hundred and forty one (741) samples were genotyped. The current frequency of the CQ-susceptible Pfcrt-K76 was above 92% and did not differ between regions in Tanzania (χ2 = 2.37; p = 0.795). The K76 allelic prevalence was between 85.7 and 93% in regions (χ2 = 7.88, p = 0.163). The CQ resistance recovery trends showed regional variability that may be caused by differences in malaria transmission intensity, but overall the trends converge as the susceptibility levels in all regions approach >90%. Conclusions CQ withdrawal in Tanzania has resulted into >90% recovery of susceptibility in ten years of withdrawal. These findings are in support of the search for CQ-based combination drugs as a possible future alternative to SP for IPTp in places where full recovery of CQ-susceptibility will be evident.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Reginald A Kavishe
- Kilimanjaro Christian Medical University College and Kilimanjaro Clinical Research Institute, Moshi, Tanzania.
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Nadjm B, Mtove G, Amos B, Hildenwall H, Najjuka A, Mtei F, Todd J, Reyburn H. Blood glucose as a predictor of mortality in children admitted to the hospital with febrile illness in Tanzania. Am J Trop Med Hyg 2013; 89:232-237. [PMID: 23817332 PMCID: PMC3741242 DOI: 10.4269/ajtmh.13-0016] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Data from a prospective study of 3,319 children ages 2 months to 5 years admitted with febrile illness to a Tanzanian district hospital were analyzed to determine the relationship of blood glucose and mortality. Hypoglycemia (blood sugar < 2.5 mmol/L and < 45 mg/dL) was found in 105 of 3,319 (3.2%) children at admission, and low-normal blood glucose (2.5–5 mmol/L and 45–90 mg/dL) was found in 773 of 3,319 (23.3%) children. Mortality was inversely related to admission blood sugar; compared with children with an admission blood glucose of > 5 mmol/L, the adjusted odds of dying were 3.3 (95% confidence interval = 2.1–5.2) and 9.8 (95% confidence interval = 5.1–19.0) among children with admission blood glucose 2.5–5 and < 2.5 mmol/L, respectively. Receiver operating characteristic (ROC) analysis suggested an optimal cutoff for admission blood sugar of < 5 mmol/L in predicting mortality (sensitivity = 57.7%, specificity = 75.2%). A cutoff for admission blood glucose of < 5 mmol/L represents a simple and clinically useful predictor of mortality in children admitted with severe febrile illness to hospital in resource-poor settings.
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Affiliation(s)
- Behzad Nadjm
- *Address correspondence to Behzad Nadjm, Oxford University Clinical Research Unit, National Hospital for Tropical Diseases, 78 Giai Phong St, Hanoi, Vietnam. E-mail:
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Mbakilwa H, Manga C, Kibona S, Mtei F, Meta J, Shoo A, Amos B, Reyburn H. Quality of malaria microscopy in 12 district hospital laboratories in Tanzania. Pathog Glob Health 2013. [PMID: 23182136 DOI: 10.1179/2047773212y.0000000052] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
BACKGROUND The WHO recommendation for parasitological diagnosis of malaria wherever possible is challenged by evidence of poor-quality microscopy in African hospitals but the reasons are not clear. METHODS All 12 of the busier district hospital laboratories from three regions of Tanzania were assessed for quality of the working environment and slide readers read 10 reference slides under exam conditions. Slides that had been routinely read were removed for expert reading. RESULTS Of 44 slide readers in the study, 39 (88.6%) correctly read >90% of the reference slides. Of 206 slides that had been routinely read, 33 (16%) were judged to be unreadable, 104 (51%) were readable with difficulty, and 69 (34%) were easily readable. Compared to expert reading of the same slide, the sensitivity of routine slide results of easily readable slides was 85.7% (95% confidence interval: 77.4-94.0), falling to 44.4% (95% confidence interval: 34.5-54.4) for slides that were 'readable with difficulty'. CONCLUSIONS The commonest cause of inaccurate results was the quality of the slide itself, correction of which is likely to be achievable within existing resources. A minority of slide readers were unable to read slides even under ideal conditions, suggesting the need for a 'slide reading licence' scheme.
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Affiliation(s)
- Hilda Mbakilwa
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania.
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Kariuki SM, Rockett K, Clark TG, Reyburn H, Agbenyega T, Taylor TE, Birbeck GL, Williams TN, Newton CRJC. The genetic risk of acute seizures in African children with falciparum malaria. Epilepsia 2013; 54:990-1001. [PMID: 23614351 PMCID: PMC3734649 DOI: 10.1111/epi.12173] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2013] [Indexed: 12/20/2022]
Abstract
Purpose It is unclear why some children with falciparum malaria develop acute seizures and what determines the phenotype of seizures. We sought to determine if polymorphisms of malaria candidate genes are associated with acute seizures. Methods Logistic regression was used to investigate genetic associations with malaria-associated seizures (MAS) and complex MAS (repetitive, prolonged, or focal seizures) in four MalariaGEN African sites, namely: Blantyre, Malawi; Kilifi, Kenya; Kumasi, Ghana; and Muheza, Tanzania. The analysis was repeated for five inheritance models (dominant, heterozygous, recessive, additive, and general) and adjusted for potential confounders and multiple testing. Key Findings Complex phenotypes of seizures constituted 71% of all admissions with MAS across the sites. MAS were strongly associated with cluster of differentiation-ligand-rs3092945 in females in Kilifi (p = 0.00068) and interleukin (IL)-17 receptor E-rs708567 in the pooled analysis across the sites (p = 0.00709). Complex MAS were strongly associated with epidermal growth factor module-containing mucin-like hormone receptor (EMR)1-rs373533 in Kumasi (p = 0.00033), but none in the pooled analysis. Focal MAS were strongly associated with IL-20 receptor A-rs1555498 in Muheza (p = 0.00016), but none in the pooled analysis. Prolonged MAS were strongly associated with complement receptor 1-rs17047660 in Kilifi (p = 0.00121) and glucose-6-phosphate dehydrogenase-rs1050828 in females in the pooled analysis (p = 0.00155). Repetitive MAS were strongly associated with EMR1-rs373533 in Kumasi (p = 0.00003) and cystic fibrosis transmembrane conductance receptor-rs17140229 in the pooled analysis (p = 0.00543). MAS with coma/cerebral malaria were strongly associated with EMR1-rs373533 in Kumasi (p = 0.00019) and IL10-rs3024500 in the pooled analysis across the sites (p = 0.00064). Significance We have identified a number of genetic associations that may explain the risk of seizures in >2,000 cases admitted to hospitals with MAS across four sites in Africa. These associations differed according to phenotype of seizures and site.
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Affiliation(s)
- Symon M Kariuki
- Kenya Medical Research Institute, Centre for Geographic Medicine Research Coast, Kilifi, Kenya.
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Maitland K, George EC, Evans JA, Kiguli S, Olupot-Olupot P, Akech SO, Opoka RO, Engoru C, Nyeko R, Mtove G, Reyburn H, Brent B, Nteziyaremye J, Mpoya A, Prevatt N, Dambisya CM, Semakula D, Ddungu A, Okuuny V, Wokulira R, Timbwa M, Otii B, Levin M, Crawley J, Babiker AG, Gibb DM. Exploring mechanisms of excess mortality with early fluid resuscitation: insights from the FEAST trial. BMC Med 2013; 11:68. [PMID: 23496872 PMCID: PMC3599745 DOI: 10.1186/1741-7015-11-68] [Citation(s) in RCA: 177] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 03/14/2013] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Early rapid fluid resuscitation (boluses) in African children with severe febrile illnesses increases the 48-hour mortality by 3.3% compared with controls (no bolus). We explored the effect of boluses on 48-hour all-cause mortality by clinical presentation at enrolment, hemodynamic changes over the first hour, and on different modes of death, according to terminal clinical events. We hypothesize that boluses may cause excess deaths from neurological or respiratory events relating to fluid overload. METHODS Pre-defined presentation syndromes (PS; severe acidosis or severe shock, respiratory, neurological) and predominant terminal clinical events (cardiovascular collapse, respiratory, neurological) were described by randomized arm (bolus versus control) in 3,141 severely ill febrile children with shock enrolled in the Fluid Expansion as Supportive Therapy (FEAST) trial. Landmark analyses were used to compare early mortality in treatment groups, conditional on changes in shock and hypoxia parameters. Competing risks methods were used to estimate cumulative incidence curves and sub-hazard ratios to compare treatment groups in terms of terminal clinical events. RESULTS Of 2,396 out of 3,141 (76%) classifiable participants, 1,647 (69%) had a severe metabolic acidosis or severe shock PS, 625 (26%) had a respiratory PS and 976 (41%) had a neurological PS, either alone or in combination. Mortality was greatest among children fulfilling criteria for all three PS (28% bolus, 21% control) and lowest for lone respiratory (2% bolus, 5% control) or neurological (3% bolus, 0% control) presentations. Excess mortality in bolus arms versus control was apparent for all three PS, including all their component features. By one hour, shock had resolved (responders) more frequently in bolus versus control groups (43% versus 32%, P <0.001), but excess mortality with boluses was evident in responders (relative risk 1.98, 95% confidence interval 0.94 to 4.17, P = 0.06) and 'non-responders' (relative risk 1.67, 95% confidence interval 1.23 to 2.28, P = 0.001), with no evidence of heterogeneity (P = 0.68). The major difference between bolus and control arms was the higher proportion of cardiogenic or shock terminal clinical events in bolus arms (n = 123; 4.6% versus 2.6%, P = 0.008) rather than respiratory (n = 61; 2.2% versus 1.3%, P = 0.09) or neurological (n = 63, 2.1% versus 1.8%, P = 0.6) terminal clinical events. CONCLUSIONS Excess mortality from boluses occurred in all subgroups of children. Contrary to expectation, cardiovascular collapse rather than fluid overload appeared to contribute most to excess deaths with rapid fluid resuscitation. These results should prompt a re-evaluation of evidence on fluid resuscitation for shock and a re-appraisal of the rate, composition and volume of resuscitation fluids. TRIAL REGISTRATION ISRCTN69856593.
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Affiliation(s)
- Kathryn Maitland
- Wellcome Trust Centre for Clinical Tropical Medicine, Department of Paediatrics, Faculty of Medicine, St Marys Campus, Norfolk Place, Imperial College, London W2 1PG, UK
- Kilifi Clinical Trials Facility, KEMRI-Wellcome Trust Research Programme, PO Box 230, Kilifi, Kenya
| | - Elizabeth C George
- Medical Research Council (MRC) Clinical Trials Unit, Aviation House, 125 Kingsway London, WC2B 6NH, UK
| | - Jennifer A Evans
- Department of Paediatrics University Hospital of Wales Heath Park, Cardiff, CF14 4XW, Wales, UK
| | - Sarah Kiguli
- Department of Paediatrics, Mulago Hospital, PO Box 7070, Makerere University, Kampala, Uganda
| | - Peter Olupot-Olupot
- Department of Paediatrics, Mbale Regional Referral Hospital Pallisa Road Zone, PO Box 921, Mbale, Uganda
| | - Samuel O Akech
- Kilifi Clinical Trials Facility, KEMRI-Wellcome Trust Research Programme, PO Box 230, Kilifi, Kenya
| | - Robert O Opoka
- Department of Paediatrics, Mulago Hospital, PO Box 7070, Makerere University, Kampala, Uganda
| | - Charles Engoru
- Department of Paediatrics, Soroti Regional Referral Hospital, PO Box 289, Soroti, Uganda
| | - Richard Nyeko
- Department of Paediatrics, St Mary's Hospital, PO Box 180, Lacor, Uganda
| | - George Mtove
- Department of Paediatrics Joint Malaria Programme, Teule Hospital, PO Box 81, Muheza, Tanzania
| | - Hugh Reyburn
- Department of Paediatrics Joint Malaria Programme, Teule Hospital, PO Box 81, Muheza, Tanzania
- Joint Malaria Programme, PO Box 2228, KCMC, Moshi, Tanzania
| | - Bernadette Brent
- Wellcome Trust Centre for Clinical Tropical Medicine, Department of Paediatrics, Faculty of Medicine, St Marys Campus, Norfolk Place, Imperial College, London W2 1PG, UK
- Kilifi Clinical Trials Facility, KEMRI-Wellcome Trust Research Programme, PO Box 230, Kilifi, Kenya
| | - Julius Nteziyaremye
- Department of Paediatrics, Mbale Regional Referral Hospital Pallisa Road Zone, PO Box 921, Mbale, Uganda
| | - Ayub Mpoya
- Kilifi Clinical Trials Facility, KEMRI-Wellcome Trust Research Programme, PO Box 230, Kilifi, Kenya
| | - Natalie Prevatt
- Wellcome Trust Centre for Clinical Tropical Medicine, Department of Paediatrics, Faculty of Medicine, St Marys Campus, Norfolk Place, Imperial College, London W2 1PG, UK
| | - Cornelius M Dambisya
- Department of Paediatrics, Mbale Regional Referral Hospital Pallisa Road Zone, PO Box 921, Mbale, Uganda
| | - Daniel Semakula
- Department of Paediatrics, Mulago Hospital, PO Box 7070, Makerere University, Kampala, Uganda
| | - Ahmed Ddungu
- Department of Paediatrics, Mulago Hospital, PO Box 7070, Makerere University, Kampala, Uganda
| | - Vicent Okuuny
- Department of Paediatrics, Soroti Regional Referral Hospital, PO Box 289, Soroti, Uganda
| | - Ronald Wokulira
- Department of Paediatrics, Soroti Regional Referral Hospital, PO Box 289, Soroti, Uganda
| | - Molline Timbwa
- Kilifi Clinical Trials Facility, KEMRI-Wellcome Trust Research Programme, PO Box 230, Kilifi, Kenya
| | - Benedict Otii
- Department of Paediatrics, St Mary's Hospital, PO Box 180, Lacor, Uganda
| | - Michael Levin
- Wellcome Trust Centre for Clinical Tropical Medicine, Department of Paediatrics, Faculty of Medicine, St Marys Campus, Norfolk Place, Imperial College, London W2 1PG, UK
| | - Jane Crawley
- Medical Research Council (MRC) Clinical Trials Unit, Aviation House, 125 Kingsway London, WC2B 6NH, UK
| | - Abdel G Babiker
- Medical Research Council (MRC) Clinical Trials Unit, Aviation House, 125 Kingsway London, WC2B 6NH, UK
| | - Diana M Gibb
- Medical Research Council (MRC) Clinical Trials Unit, Aviation House, 125 Kingsway London, WC2B 6NH, UK
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Hendriksen ICE, White LJ, Veenemans J, Mtove G, Woodrow C, Amos B, Saiwaew S, Gesase S, Nadjm B, Silamut K, Joseph S, Chotivanich K, Day NPJ, von Seidlein L, Verhoef H, Reyburn H, White NJ, Dondorp AM. Defining falciparum-malaria-attributable severe febrile illness in moderate-to-high transmission settings on the basis of plasma PfHRP2 concentration. J Infect Dis 2013; 207:351-61. [PMID: 23136222 PMCID: PMC3532834 DOI: 10.1093/infdis/jis675] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 08/23/2012] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND In malaria-endemic settings, asymptomatic parasitemia complicates the diagnosis of malaria. Histidine-rich protein 2 (HRP2) is produced by Plasmodium falciparum, and its plasma concentration reflects the total body parasite burden. We aimed to define the malaria-attributable fraction of severe febrile illness, using the distributions of plasma P. falciparum HRP2 (PfHRP2) concentrations from parasitemic children with different clinical presentations. METHODS Plasma samples were collected from and peripheral blood slides prepared for 1435 children aged 6-60 months in communities and a nearby hospital in northeastern Tanzania. The study population included children with severe or uncomplicated malaria, asymptomatic carriers, and healthy control subjects who had negative results of rapid diagnostic tests. The distributions of plasma PfHRP2 concentrations among the different groups were used to model severe malaria-attributable disease. RESULTS The plasma PfHRP2 concentration showed a close correlation with the severity of infection. PfHRP2 concentrations of >1000 ng/mL denoted a malaria-attributable fraction of severe disease of 99% (95% credible interval [CI], 96%-100%), with a sensitivity of 74% (95% CI, 72%-77%), whereas a concentration of <200 ng/mL denoted severe febrile illness of an alternative diagnosis in >10% (95% CI, 3%-27%) of patients. Bacteremia was more common among patients in the lowest and highest PfHRP2 concentration quintiles. CONCLUSIONS The plasma PfHRP2 concentration defines malaria-attributable disease and distinguishes severe malaria from coincidental parasitemia in African children in a moderate-to-high transmission setting.
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Affiliation(s)
- Ilse C E Hendriksen
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
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Abstract
BACKGROUND While child mortality is declining in Africa there has been no evidence of a comparable reduction in neonatal mortality. The quality of inpatient neonatal care is likely a contributing factor but data from resource limited settings are few. The objective of this study was to assess the quality of neonatal care in the district hospitals of the Kilimanjaro region of Tanzania. METHODS Clinical records were reviewed for ill or premature neonates admitted to 13 inpatient health facilities in the Kilimanjaro region; staffing and equipment levels were also assessed. RESULTS Among the 82 neonates reviewed, key health information was missing from a substantial proportion of records: on maternal antenatal cards, blood group was recorded for 52 (63.4%) mothers, Rhesus (Rh) factor for 39 (47.6%), VDRL for 59 (71.9%) and HIV status for 77 (93.1%). From neonatal clinical records, heart rate was recorded for3 (3.7%) neonates, respiratory rate in 14, (17.1%) and temperature in 33 (40.2%). None of 13 facilities had a functioning premature unit despite calculated gestational age <36 weeks in 45.6% of evaluated neonates. Intravenous fluids and oxygen were available in 9 out of 13 of facilities, while antibiotics and essential basic equipment were available in more than two thirds. Medication dosing errors were common; under-dosage for ampicillin, gentamicin and cloxacillin was found in 44.0%, 37.9% and 50% of cases, respectively, while over-dosage was found in 20.0%, 24.2% and 19.9%, respectively. Physician or assistant physician staffing levels by the WHO indicator levels (WISN) were generally low. CONCLUSION Key aspects of neonatal care were found to be poorly documented or incorrectly implemented in this appraisal of neonatal care in Kilimanjaro. Efforts towards quality assurance and enhanced motivation of staff may improve outcomes for this vulnerable group.
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Affiliation(s)
- Bernard Mbwele
- Kilimanjaro Clinical Research Institute, P.O Box 2236, Moshi, Tanzania
| | - Elizabeth Reddy
- Duke University Dept. of Medicine; Division of Infectious Disease, Kilimanjaro Christian Medical Centre-Duke University Collaboration, P.O Box 3010, Moshi, Tanzania
| | - Hugh Reyburn
- London school of Hygiene and Tropical Medicine, Disease Control Dept, Faculty of Infectious and Tropical Disease, London School of Hygiene and Tropical Medicine, Keppel St, London, WCIE 7HT, UK
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Manjurano A, Clark TG, Nadjm B, Mtove G, Wangai H, Sepulveda N, Campino SG, Maxwell C, Olomi R, Rockett KR, Jeffreys A, Riley EM, Reyburn H, Drakeley C. Candidate human genetic polymorphisms and severe malaria in a Tanzanian population. PLoS One 2012; 7:e47463. [PMID: 23144702 PMCID: PMC3483265 DOI: 10.1371/journal.pone.0047463] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 09/12/2012] [Indexed: 11/18/2022] Open
Abstract
Human genetic background strongly influences susceptibility to malaria infection and progression to severe disease and death. Classical genetic studies identified haemoglobinopathies and erythrocyte-associated polymorphisms, as protective against severe disease. High throughput genotyping by mass spectrometry allows multiple single nucleotide polymorphisms (SNPs) to be examined simultaneously. We compared the prevalence of 65 human SNP's, previously associated with altered risk of malaria, between Tanzanian children with and without severe malaria. Five hundred children, aged 1–10 years, with severe malaria were recruited from those admitted to hospital in Muheza, Tanzania and compared with matched controls. Genotyping was performed by Sequenom MassArray, and conventional PCR was used to detect deletions in the alpha-thalassaemia gene. SNPs in two X-linked genes were associated with altered risk of severe malaria in females but not in males: heterozygosity for one or other of two SNPs in the G6PD gene was associated with protection from all forms of severe disease whilst two SNPs in the gene encoding CD40L were associated with respiratory distress. A SNP in the adenyl cyclase 9 (ADCY9) gene was associated with protection from acidosis whilst a polymorphism in the IL-1α gene (IL1A) was associated with an increased risk of acidosis. SNPs in the genes encoding IL-13 and reticulon-3 (RTN3) were associated with increased risk of cerebral malaria. This study confirms previously known genetic associations with protection from severe malaria (HbS, G6PD). It identifies two X-linked genes associated with altered risk of severe malaria in females, identifies mutations in ADCY9, IL1A and CD40L as being associated with altered risk of severe respiratory distress and acidosis, both of which are characterised by high serum lactate levels, and also identifies novel genetic associations with severe malaria (TRIM5) and cerebral malaria(IL-13 and RTN3). Further studies are required to test the generality of these associations and to understand their functional consequences.
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Affiliation(s)
- Alphaxard Manjurano
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Taane G. Clark
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Behzad Nadjm
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - George Mtove
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Hannah Wangai
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Nuno Sepulveda
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Caroline Maxwell
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Raimos Olomi
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
| | - Kirk R. Rockett
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Anna Jeffreys
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | | | - Eleanor M. Riley
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Hugh Reyburn
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Christopher Drakeley
- Joint Malaria Programme, Kilimanjaro Christian Medical Centre, Moshi, Tanzania
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom
- * E-mail:
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Buchanan AM, Nadjm B, Amos B, Mtove G, Sifuna D, Cunningham CK, Crump JA, Reyburn H. Utility of rapid antibody tests to exclude HIV-1 infection among infants and children aged <18 months in a low-resource setting. J Clin Virol 2012; 55:244-9. [PMID: 22925720 DOI: 10.1016/j.jcv.2012.08.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2012] [Revised: 06/20/2012] [Accepted: 08/01/2012] [Indexed: 10/28/2022]
Abstract
BACKGROUND Excluding HIV infection among infants and young children in resource-poor settings where nucleic acid amplification tests (NAAT) are not routinely available remains a considerable challenge. OBJECTIVES To assess the performance of two rapid HIV antibody tests (RT) used alone and in parallel for excluding HIV infection among acutely ill infants and children <18 months in comparison to NAAT in a region where maternal HIV prevalence was approximately 7%. STUDY DESIGN Infants and children ≥2<18 months admitted to hospital with an acute febrile illness had two rapid antibody tests in parallel, with single and parallel results subsequently compared against NAAT. RESULTS HIV prevalence among 1602 enrolled infants was 3.4%. All 1526 infants with 2 negative RT were HIV negative by NAAT. All 46 infants with 2 positive RT were HIV positive by NAAT. The overall specificity of two rapid tests for excluding HIV infection was 99.5%. Sensitivity and specificity were ≥99% and >98%, respectively, across all age brackets ≥2<18 months. Overall sensitivity and specificity for a single RT was 98.2% and 99%, respectively, for Determine, and 85.5% and 99.6%, respectively, for Capillus. CONCLUSIONS In a setting with a maternal HIV prevalence rate of <10%, a single negative RT had excellent specificity and two negative RT performed in parallel had a perfect negative predictive value for HIV infection among acutely ill patients <18 months of age. In this and similar settings, RT could assist with excluding HIV infection with much lower complexity and cost than NAAT.
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Affiliation(s)
- Ann M Buchanan
- Division of Infectious Diseases, Department of Pediatrics, Duke University Medical Center, Durham, NC, USA.
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Ramutton T, Hendriksen ICE, Mwanga-Amumpaire J, Mtove G, Olaosebikan R, Tshefu AK, Onyamboko MA, Karema C, Maitland K, Gomes E, Gesase S, Reyburn H, Silamut K, Chotivanich K, Promnares K, Fanello CI, von Seidlein L, Day NPJ, White NJ, Dondorp AM, Imwong M, Woodrow CJ. Sequence variation does not confound the measurement of plasma PfHRP2 concentration in African children presenting with severe malaria. Malar J 2012; 11:276. [PMID: 22898068 PMCID: PMC3480887 DOI: 10.1186/1475-2875-11-276] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 08/13/2012] [Indexed: 11/12/2022] Open
Abstract
Background Plasmodium falciparum histidine-rich protein PFHRP2 measurement is used widely for diagnosis, and more recently for severity assessment in falciparum malaria. The Pfhrp2 gene is highly polymorphic, with deletion of the entire gene reported in both laboratory and field isolates. These issues potentially confound the interpretation of PFHRP2 measurements. Methods Studies designed to detect deletion of Pfhrp2 and its paralog Pfhrp3 were undertaken with samples from patients in seven countries contributing to the largest hospital-based severe malaria trial (AQUAMAT). The quantitative relationship between sequence polymorphism and PFHRP2 plasma concentration was examined in samples from selected sites in Mozambique and Tanzania. Results There was no evidence for deletion of either Pfhrp2 or Pfhrp3 in the 77 samples with lowest PFHRP2 plasma concentrations across the seven countries. Pfhrp2 sequence diversity was very high with no haplotypes shared among 66 samples sequenced. There was no correlation between Pfhrp2 sequence length or repeat type and PFHRP2 plasma concentration. Conclusions These findings indicate that sequence polymorphism is not a significant cause of variation in PFHRP2 concentration in plasma samples from African children. This justifies the further development of plasma PFHRP2 concentration as a method for assessing African children who may have severe falciparum malaria. The data also add to the existing evidence base supporting the use of rapid diagnostic tests based on PFHRP2 detection.
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Affiliation(s)
- Thiranut Ramutton
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
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von Seidlein L, Olaosebikan R, Hendriksen ICE, Lee SJ, Adedoyin OT, Agbenyega T, Nguah SB, Bojang K, Deen JL, Evans J, Fanello CI, Gomes E, Pedro AJ, Kahabuka C, Karema C, Kivaya E, Maitland K, Mokuolu OA, Mtove G, Mwanga-Amumpaire J, Nadjm B, Nansumba M, Ngum WP, Onyamboko MA, Reyburn H, Sakulthaew T, Silamut K, Tshefu AK, Umulisa N, Gesase S, Day NPJ, White NJ, Dondorp AM. Predicting the clinical outcome of severe falciparum malaria in african children: findings from a large randomized trial. Clin Infect Dis 2012; 54:1080-90. [PMID: 22412067 PMCID: PMC3309889 DOI: 10.1093/cid/cis034] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Four predictors were independently associated with an increased risk of death: acidosis, cerebral manifestations of malaria, elevated blood urea nitrogen, or signs of chronic illness. The standard base deficit was found to be the single most relevant predictor of death. Background. Data from the largest randomized, controlled trial for the treatment of children hospitalized with severe malaria were used to identify such predictors of a poor outcome from severe malaria. Methods. African children (<15 years) with severe malaria participated in a randomized comparison of parenteral artesunate and parenteral quinine in 9 African countries. Detailed clinical assessment was performed on admission. Parasite densities were assessed in a reference laboratory. Predictors of death were examined using a multivariate logistic regression model. Results. Twenty indicators of disease severity were assessed, out of which 5 (base deficit, impaired consciousness, convulsions, elevated blood urea, and underlying chronic illness) were associated independently with death. Tachypnea, respiratory distress, deep breathing, shock, prostration, low pH, hyperparasitemia, severe anemia, and jaundice were statistically significant indicators of death in the univariate analysis but not in the multivariate model. Age, glucose levels, axillary temperature, parasite density, heart rate, blood pressure, and blackwater fever were not related to death in univariate models. Conclusions. Acidosis, cerebral involvement, renal impairment, and chronic illness are key independent predictors for a poor outcome in African children with severe malaria. Mortality is markedly increased in cerebral malaria combined with acidosis. Clinical Trial Registration. ISRCTN50258054.
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Affiliation(s)
- Lorenz von Seidlein
- Department of Global Health, Menzies School of Health Research, Casuarina, Northern Territory, Australia.
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Mtove G, Nadjm B, Hendriksen ICE, Amos B, Muro F, Todd J, Reyburn H. Point-of-care measurement of blood lactate in children admitted with febrile illness to an African District Hospital. Clin Infect Dis 2012; 53:548-54. [PMID: 21865191 DOI: 10.1093/cid/cir471] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Lactic acidosis is a consistent predictor of mortality owing to severe infectious disease, but its detection in low-income settings is limited to the clinical sign of "deep breathing" because of the lack of accessible technology for its measurement. We evaluated the use of a point-of-care (POC) diagnostic device for blood lactate measurement to assess the severity of illness in children admitted to a district hospital in Tanzania. METHODS Children between the ages of 2 months and 13 years with a history of fever were enrolled in the study during a period of 1 year. A full clinical history and examination were undertaken, and blood was collected for culture, microscopy, complete blood cell count, and POC measurement of blood lactate and glucose. RESULTS The study included 3248 children, of whom 164 (5.0%) died; 45 (27.4%) of these had raised levels of blood lactate (>5 mmol/L) but no deep breathing. Compared with mortality in children with lactate levels of ≤ 3 mmol/L, the unadjusted odds of dying were 1.6 (95% confidence interval [CI].8-3.0), 3.4 (95% CI, 1.5-7.5), and 8.9 (95% CI, 4.7-16.8) in children with blood lactate levels of 3.1-5.0, 5.1-8.0, or >8.0 mmol/L, respectively. The prevalence of raised lactate levels (>5 mmol/L) was greater in children with malaria than in children with nonmalarial febrile illness (P < .001) although the associated mortality was greater in slide-negative children. CONCLUSIONS POC lactate measurement can contribute to the assessment of children admitted to hospital with febrile illness and can also create an opportunity for more hospitals in resource-poor settings to participate in clinical trials of interventions to reduce mortality associated with hyperlactatemia.
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Affiliation(s)
- George Mtove
- National Institute for Medical Research, Amani Centre, Tanzania
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Hendriksen ICE, Mwanga-Amumpaire J, von Seidlein L, Mtove G, White LJ, Olaosebikan R, Lee SJ, Tshefu AK, Woodrow C, Amos B, Karema C, Saiwaew S, Maitland K, Gomes E, Pan-Ngum W, Gesase S, Silamut K, Reyburn H, Joseph S, Chotivanich K, Fanello CI, Day NPJ, White NJ, Dondorp AM. Diagnosing severe falciparum malaria in parasitaemic African children: a prospective evaluation of plasma PfHRP2 measurement. PLoS Med 2012; 9:e1001297. [PMID: 22927801 PMCID: PMC3424256 DOI: 10.1371/journal.pmed.1001297] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 07/13/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND In African children, distinguishing severe falciparum malaria from other severe febrile illnesses with coincidental Plasmodium falciparum parasitaemia is a major challenge. P. falciparum histidine-rich protein 2 (PfHRP2) is released by mature sequestered parasites and can be used to estimate the total parasite burden. We investigated the prognostic significance of plasma PfHRP2 and used it to estimate the malaria-attributable fraction in African children diagnosed with severe malaria. METHODS AND FINDINGS Admission plasma PfHRP2 was measured prospectively in African children (from Mozambique, The Gambia, Kenya, Tanzania, Uganda, Rwanda, and the Democratic Republic of the Congo) aged 1 month to 15 years with severe febrile illness and a positive P. falciparum lactate dehydrogenase (pLDH)-based rapid test in a clinical trial comparing parenteral artesunate versus quinine (the AQUAMAT trial, ISRCTN 50258054). In 3,826 severely ill children, Plasmadium falciparum PfHRP2 was higher in patients with coma (p = 0.0209), acidosis (p<0.0001), and severe anaemia (p<0.0001). Admission geometric mean (95%CI) plasma PfHRP2 was 1,611 (1,350-1,922) ng/mL in fatal cases (n = 381) versus 1,046 (991-1,104) ng/mL in survivors (n = 3,445, p<0.0001), without differences in parasitaemia as assessed by microscopy. There was a U-shaped association between log(10) plasma PfHRP2 and risk of death. Mortality increased 20% per log(10) increase in PfHRP2 above 174 ng/mL (adjusted odds ratio [AOR] 1.21, 95%CI 1.05-1.39, p = 0.009). A mechanistic model assuming a PfHRP2-independent risk of death in non-malaria illness closely fitted the observed data and showed malaria-attributable mortality less than 50% with plasma PfHRP2≤174 ng/mL. The odds ratio (OR) for death in artesunate versus quinine-treated patients was 0.61 (95%CI 0.44-0.83, p = 0.0018) in the highest PfHRP2 tertile, whereas there was no difference in the lowest tertile (OR 1.05; 95%CI 0.69-1.61; p = 0.82). A limitation of the study is that some conclusions are drawn from a mechanistic model, which is inherently dependent on certain assumptions. However, a sensitivity analysis of the model indicated that the results were robust to a plausible range of parameter estimates. Further studies are needed to validate our findings. CONCLUSIONS Plasma PfHRP2 has prognostic significance in African children with severe falciparum malaria and provides a tool to stratify the risk of "true" severe malaria-attributable disease as opposed to other severe illnesses in parasitaemic African children.
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Affiliation(s)
- Ilse C. E. Hendriksen
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | | | | | - George Mtove
- National Institute for Medical Research, Amani Centre, Tanga, Tanzania
| | - Lisa J. White
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | | | - Sue J. Lee
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | - Antoinette K. Tshefu
- Kinshasa School of Public Health, Kingasani Research Centre, Kinshasa, Democratic Republic of the Congo
| | - Charles Woodrow
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | - Ben Amos
- Teule Hospital, Muheza, Tanzania
| | - Corine Karema
- Malaria Control Program, Ministry of Health, Kigali, Rwanda
| | - Somporn Saiwaew
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Kathryn Maitland
- Kenya Medical Research Institute (KEMRI)–Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Wirichada Pan-Ngum
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Samwel Gesase
- National Institute for Medical Research, Tanga Medical Research Centre, Tanga, Tanzania
| | - Kamolrat Silamut
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Hugh Reyburn
- London School of Tropical Medicine & Hygiene, London, United Kingdom
| | - Sarah Joseph
- Medical Research Council, London, United Kingdom
| | - Kesinee Chotivanich
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Caterina I. Fanello
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | - Nicholas P. J. Day
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | - Nicholas J. White
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
| | - Arjen M. Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Centre for Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, United Kingdom
- * E-mail:
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Manjurano A, Okell L, Lukindo T, Reyburn H, Olomi R, Roper C, Clark TG, Joseph S, Riley EM, Drakeley C. Association of sub-microscopic malaria parasite carriage with transmission intensity in north-eastern Tanzania. Malar J 2011; 10:370. [PMID: 22177014 PMCID: PMC3276450 DOI: 10.1186/1475-2875-10-370] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 12/16/2011] [Indexed: 11/25/2022] Open
Abstract
Background In malaria endemic areas, individuals are frequently asymptomatic and may be undetected by conventional microscopy or newer, rapid diagnostic tests. Molecular techniques allow a more accurate assessment of this asymptomatic parasite burden, the extent of which is important for malaria control. This study examines the relative prevalence of sub-microscopic level parasite carriage and clonal complexity of infections (multiplicity of infection) over a range of endemicities in a region of north-eastern Tanzania where altitude is an established proxy of malaria transmission. The PCR prevalence was then compared against other measures of transmission intensity collected in the same area. Methods This study used 1,121 blood samples collected from a previously conducted cross-sectional malario-metric survey during the short rainy season in 2001 from 13 villages (three at < 600 m, four at 600-1,200 m and six at > 1,200 m in altitude above sea level). Samples were analysed by PCR for carriage of parasites and multiplicity of infection. These data were compared with other measures of transmission intensity collected from the same area. Results Parasite prevalence was 34.7% by PCR and 13.6% by microscopy; a 2.5-fold difference in line with other recent observations. This fold difference was relatively consistent at the different altitude bands despite a marked decrease in parasite prevalence with altitude: < 600 m 70.9 vs 28.6, 600-1,200 m 35.5 vs 9.9, > 1,200 m 15.8 vs 5.9. The difference between parasite prevalence by PCR was 3.2 in individuals aged between 15 and 45 years (34.5 vs 10.9) compared with 2.5 in those aged 1-5 (34.0 vs 13.5) though this was not statistically significant. Multiplicity of infection (MOI) ranged from 1.2 to 3.7 and was positively associated with parasite prevalence assessed by both PCR and microscopy. There was no association of MOI and age. Village level PCR parasite prevalence was strongly correlated with altitude, sero-conversion rate and predicted entomological inoculation rate. Conclusions Asymptomatic, low density, multi-clone malaria infection was common in this study area. These infections are important as potential contributors to the infectious reservoir of parasites and need to be identified by control programmes especially in this era where malaria elimination is a focus. High throughput standardized PCR approaches are needed to identify individuals who are malaria carriers.
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Affiliation(s)
- Alphaxard Manjurano
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, WC1E 7HT, London, UK
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50
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Mtove G, Amos B, Nadjm B, Hendriksen ICE, Dondorp AM, Mwambuli A, Kim DR, Ochiai RL, Clemens JD, von Seidlein L, Reyburn H, Deen J. Decreasing incidence of severe malaria and community-acquired bacteraemia among hospitalized children in Muheza, north-eastern Tanzania, 2006-2010. Malar J 2011; 10:320. [PMID: 22029477 PMCID: PMC3219788 DOI: 10.1186/1475-2875-10-320] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Accepted: 10/27/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The annual incidence and temporal trend of severe malaria and community-acquired bacteraemia during a four-year period in Muheza, Tanzania was assessed. METHODS Data on severely ill febrile children aged 2 months to 14 years from three prospective studies conducted at Muheza District Hospital from 2006 to 2010 was pooled and analysed. On admission, each enrolled child had a thin and thick blood film and at least one rapid diagnostic test for falciparum malaria, as well as a blood culture. The annual incidence of bacteraemia and severe malaria among children coming from Muheza was calculated and their temporal trend was assessed. RESULTS Overall, 1, 898 severe falciparum malaria and 684 bacteraemia cases were included. Of these, 1, 356 (71%) and 482 (71%), respectively, were from the referral population of Muheza. The incidence of falciparum malaria and all-cause bacteraemia in Muheza decreased five-fold and three-fold, respectively, from the first to the fourth year of surveillance (p < 0.0001). During this period, the median ages of children from Muheza admitted with severe malaria increased from 1.7 to 2.5 years (p < 0.0001). The reduction in all-cause bacteraemia was mainly driven by the 11-fold decline in the incidence of non-typhoidal salmonellosis. The annual incidences of Haemophilus influenzae and pneumococcal invasive bacterial infections decreased as well but were much fewer in number. CONCLUSIONS These results add to the growing evidence of the decline in malaria associated with a decrease in non-typhoidal salmonellosis and possibly other bacteraemias. Malarial prevention and control strategies may provide a greater benefit than the mere reduction of malaria alone.
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Affiliation(s)
- George Mtove
- National Institute for Medical Research - Amani Centre, Tanga, Tanzania
- Joint Malaria Programme, Moshi, Tanzania
| | - Ben Amos
- Joint Malaria Programme, Moshi, Tanzania
- Teule Hospital, Muheza, Tanga, Tanzania
| | - Behzad Nadjm
- Joint Malaria Programme, Moshi, Tanzania
- London School of Hygiene and Tropical Medicine, London, UK
| | - Ilse CE Hendriksen
- Joint Malaria Programme, Moshi, Tanzania
- Mahidol-Oxford Research Unit, Bangkok, Thailand
| | | | | | - Deok Ryun Kim
- International Vaccine Institute, SNU Research Park, San 4-8, Nakseongdae-dong, Gwanak-gu, Seoul, Korea
| | - R Leon Ochiai
- International Vaccine Institute, SNU Research Park, San 4-8, Nakseongdae-dong, Gwanak-gu, Seoul, Korea
| | - John D Clemens
- International Vaccine Institute, SNU Research Park, San 4-8, Nakseongdae-dong, Gwanak-gu, Seoul, Korea
| | - Lorenz von Seidlein
- Joint Malaria Programme, Moshi, Tanzania
- Menzies School of Health Research, Casuarina, NT, Australia
| | - Hugh Reyburn
- Joint Malaria Programme, Moshi, Tanzania
- London School of Hygiene and Tropical Medicine, London, UK
| | - Jacqueline Deen
- Joint Malaria Programme, Moshi, Tanzania
- International Vaccine Institute, SNU Research Park, San 4-8, Nakseongdae-dong, Gwanak-gu, Seoul, Korea
- Menzies School of Health Research, Casuarina, NT, Australia
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