1
|
Popkin-Hall ZR, Seth MD, Madebe RA, Budodo R, Bakari C, Francis F, Pereus D, Giesbrecht DJ, Mandara CI, Mbwambo D, Aaron S, Lusasi A, Lazaro S, Bailey JA, Juliano JJ, Ishengoma DS. Malaria Species Positivity Rates Among Symptomatic Individuals Across Regions of Differing Transmission Intensities in Mainland Tanzania. J Infect Dis 2024; 229:959-968. [PMID: 37992117 PMCID: PMC11011190 DOI: 10.1093/infdis/jiad522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/09/2023] [Accepted: 11/20/2023] [Indexed: 11/24/2023] Open
Abstract
BACKGROUND Recent data indicate that non-Plasmodium falciparum species may be more prevalent than thought in sub-Saharan Africa. Although Plasmodium malariae, Plasmodium ovale spp., and Plasmodium vivax are less severe than P. falciparum, treatment and control are more challenging, and their geographic distributions are not well characterized. METHODS We randomly selected 3284 of 12 845 samples collected from cross-sectional surveys in 100 health facilities across 10 regions of Mainland Tanzania and performed quantitative real-time PCR to determine presence and parasitemia of each malaria species. RESULTS P. falciparum was most prevalent, but P. malariae and P. ovale were found in all but 1 region, with high levels (>5%) of P. ovale in 7 regions. The highest P. malariae positivity rate was 4.5% in Mara and 8 regions had positivity rates ≥1%. We only detected 3 P. vivax infections, all in Kilimanjaro. While most nonfalciparum malaria-positive samples were coinfected with P. falciparum, 23.6% (n = 13 of 55) of P. malariae and 14.7% (n = 24 of 163) of P. ovale spp. were monoinfections. CONCLUSIONS P. falciparum remains by far the largest threat, but our data indicate that malaria elimination efforts in Tanzania will require increased surveillance and improved understanding of the biology of nonfalciparum species.
Collapse
Affiliation(s)
- Zachary R Popkin-Hall
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Misago D Seth
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Rashid A Madebe
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Rule Budodo
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Catherine Bakari
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - Filbert Francis
- National Institute for Medical Research, Tanga Center, Tanga, Tanzania
| | - Dativa Pereus
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | - David J Giesbrecht
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Celine I Mandara
- National Institute for Medical Research, Dar es Salaam, Tanzania
| | | | | | | | - Samwel Lazaro
- National Malaria Control Programme, Dodoma, Tanzania
| | - Jeffrey A Bailey
- Department of Pathology and Laboratory Medicine, Warren Alpert Medical School, Brown University, Providence, Rhode Island, USA
- Center for Computational Molecular Biology, Brown University, Providence, Rhode Island, USA
| | - Jonathan J Juliano
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Deus S Ishengoma
- National Institute for Medical Research, Dar es Salaam, Tanzania
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
- Faculty of Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia
| |
Collapse
|
2
|
Gaither C, Morgan C, Kirby R, Karema C, Gashema P, White SJ, Topazian HM, Geibrecht D, Thwai K, Boyter K, Munyaneza T, Muvunyi CM, De Dieu Butera J, Bailey JA, Mazarati JB, Juliano JJ. Prevalence of Falciparum and non-Falciparum Malaria in the 2014-15 Rwanda Demographic Health Survey. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.01.09.24301054. [PMID: 38260604 PMCID: PMC10802648 DOI: 10.1101/2024.01.09.24301054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Background Malaria remains a major cause of morbidity in sub-Saharan Africa. Undetected asymptomatic falciparum malaria results in a large transmission reservoir and there is evidence of increasing non-falciparum malaria as malaria is controlled in Africa, both resulting in challenges for malaria control programs. Methods We performed quantitative real time PCR for 4 malaria species in 4,596 individuals from the 2014-2015 Rwanda Demographic Health Survey. Bivariate models were used to determine species-specific associations with risk factors. Results Asymptomatic falciparum malaria, P. ovale spp., and P. malariae infection had broad spatial distribution across Rwanda. P. vivax infection was rare. Overall infection prevalence was 23.6% (95%CI [21.7%, 26.0%]), with falciparum and non-falciparum at 17.6% [15.9%, 19.0%] and 8.3% [7.0%, 10.0%], respectively. Parasitemias tended to be low and mixed species infections were common, especially where malaria transmission was the highest. Falciparum infection was associated with socio-econiomic status, rural residence and low altitude. Few risk factors were associated with non-falciparum malaria. Conclusions Asymptomatic falciparum malaria and non-falciparum malaria are common and widely distributed across Rwanda. Continued molecular monitoring of Plasmodium spp. is needed to monitor these threats to malaria control in Africa.
Collapse
Affiliation(s)
- Claudia Gaither
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, NC, USA
| | - Camille Morgan
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Rebecca Kirby
- Department of Pathology, Brown University, Providence, RI, USA
| | | | | | - Samuel J White
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, NC, USA
| | - Hillary M Topazian
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, UK
| | - David Geibrecht
- Department of Pathology, Brown University, Providence, RI, USA
| | - Kyaw Thwai
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, NC, USA
| | - Koby Boyter
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, NC, USA
| | | | | | | | | | | | - Jonathan J Juliano
- Institute for Global Health and Infectious Diseases, University of North Carolina, Chapel Hill, NC, USA
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC, USA
- Division of Infectious Diseases, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
- Curriculum in Genetics and Molecular Biology, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| |
Collapse
|
3
|
Stanley CC, Zulu M, Msuku H, Phiri VS, Kazembe LN, Chinkhumba J, Mvalo T, Mathanga DP. Competing risks modeling of length of hospital stay enhances risk-stratification of patient care: application to under-five children hospitalized in Malawi. FRONTIERS IN EPIDEMIOLOGY 2023; 3:1274776. [PMID: 38455913 PMCID: PMC10911049 DOI: 10.3389/fepid.2023.1274776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Accepted: 10/26/2023] [Indexed: 03/09/2024]
Abstract
Introduction Length of hospital stay (LOS), defined as the time from inpatient admission to discharge, death, referral, or abscondment, is one of the key indicators of quality in patient care. Reduced LOS lowers health care expenditure and minimizes the chance of in-hospital acquired infections. Conventional methods for estimating LOS such as the Kaplan-Meier survival curve and the Cox proportional hazards regression for time to discharge cannot account for competing risks such as death, referral, and abscondment. This study applied competing risk methods to investigate factors important for risk-stratifying patients based on LOS in order to enhance patient care. Methods This study analyzed data from ongoing safety surveillance of the malaria vaccine implementation program in Malawi's four district hospitals of Balaka, Machinga, Mchinji, and Ntchisi. Children aged 1-59 months who were hospitalized (spending at least one night in hospital) with a medical illness were consecutively enrolled between 1 November 2019 and 31 July 2021. Sub-distribution-hazard (SDH) ratios for the cumulative incidence of discharge were estimated using the Fine-Gray competing risk model. Results Among the 15,463 children hospitalized, 8,607 (55.7%) were male and 6,856 (44.3%) were female. The median age was 22 months [interquartile range (IQR): 12-33 months]. The cumulative incidence of discharge was 40% lower among HIV-positive children compared to HIV-negative (sub-distribution-hazard ratio [SDHR]: 0.60; [95% CI: 0.46-0.76]; P < 0.001); lower among children with severe and cerebral malaria [SDHR: 0.94; (95% CI: 0.86-0.97); P = 0.04], sepsis or septicemia [SDHR: 0.90; (95% CI: 0.82-0.98); P = 0.027], severe anemia related to malaria [SDHR: 0.54; (95% CI: 0.48-0.61); P < 0.001], and meningitis [SDHR: 0.18; (95% CI: 0.09-0.37); P < 0.001] when compared to non-severe malaria; and also 39% lower among malnourished children compared to those that were well-nourished [SDHR: 0.61; (95% CI: 0.55-0.68); P < 0.001]. Conclusions This study applied the Fine-Gray competing risk approach to more accurately model LOS as the time to discharge when there were significant rates of in-hospital mortality, referrals, and abscondment. Patient care can be enhanced by risk-stratifying by LOS based on children's age, HIV status, diagnosis, and nutritional status.
Collapse
Affiliation(s)
- Christopher C. Stanley
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Blantyre, Malawi
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Madalitso Zulu
- University of North Carolina Project Malawi, Lilongwe, Malawi
| | - Harrison Msuku
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Vincent S. Phiri
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Lawrence N. Kazembe
- Department of Computing, Mathematical and Statistical Sciences, University of Namibia, Windhoek, Namibia
| | - Jobiba Chinkhumba
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Blantyre, Malawi
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Tisungane Mvalo
- University of North Carolina Project Malawi, Lilongwe, Malawi
- Department of Pediatrics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Don P. Mathanga
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Blantyre, Malawi
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| |
Collapse
|
4
|
He W, Sendor R, Potlapalli VR, Kashamuka MM, Tshefu AK, Phanzu F, Kalonji A, Ngasala B, Thwai KL, Juliano JJ, Lin JT, Parr JB. A novel duplex qualitative real-time PCR assay for the detection and differentiation of Plasmodium ovale curtisi and Plasmodium ovale wallikeri malaria. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.10.31.23297819. [PMID: 37961397 PMCID: PMC10635243 DOI: 10.1101/2023.10.31.23297819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
Background P. ovale spp. infections are endemic across multiple African countries and are caused by two distinct non-recombining species, P. ovale curtisi (Poc) and P. ovale wallikeri (Pow). These species are thought to differ in clinical symptomatology and latency, but existing diagnostic assays have limited ability to detect and distinguish them. In this study, we developed a new duplex assay for the detection and differentiation of Poc and Pow that can be used to improve our understanding of these parasites. Methods Repetitive sequence motifs were identified in available Poc and Pow genomes and used for assay development and validation. We evaluated the analytical sensitivity and specificity of the best-performing assay using a panel of samples from Tanzania and the Democratic Republic of the Congo (DRC), then validated its performance using 55 P. ovale spp. samples and 40 non-ovale Plasmodium samples from the DRC. Poc and Pow prevalence among symptomatic individuals sampled across three provinces of the DRC were estimated. Results The best-performing Poc and Pow targets had 9 and 8 copies within the reference genomes, respectively. Our duplex assay had 100% specificity and 95% confidence lower limits of detection of 4.2 and 41.2 parasite genome equivalents/μl for Poc and Pow, respectively. Species was determined in 80% of all P. ovale spp.-positive field samples and 100% of those with >10 parasites/μl. Most P. ovale spp. field samples from the DRC were found to be Poc infections. Conclusions We identified promising multi-copy targets for molecular detection and differentiation of Poc and Pow and used them to develop a new duplex real-time PCR assay that performed well when applied to diverse field samples. Though low-density Pow infections are not reliably detected, the assay is highly specific and can be used for high-throughput studies of P. ovale spp. epidemiology among symptomatic cases in malaria-endemic countries like the DRC.
Collapse
Affiliation(s)
- Wenqiao He
- Division of Infectious Diseases and Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Epidemiology, School of Public Health, Guangdong Provincial Key Laboratory of Tropical Disease Research, Southern Medical University, Guangzhou, China
| | - Rachel Sendor
- Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, NC, United States
| | - Varun R. Potlapalli
- Division of Infectious Diseases and Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | | | | | | | | | - Billy Ngasala
- Muhimbili University of Health and Allied Sciences, Dar Es Salaam, Tanzania
| | - Kyaw Lay Thwai
- Division of Infectious Diseases and Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Jonathan J. Juliano
- Division of Infectious Diseases and Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
- Department of Epidemiology, Gillings School of Global Public Health, Chapel Hill, NC, United States
| | - Jessica T. Lin
- Division of Infectious Diseases and Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| | - Jonathan B. Parr
- Division of Infectious Diseases and Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, United States
| |
Collapse
|
5
|
Sendor R, Banek K, Kashamuka MM, Mvuama N, Bala JA, Nkalani M, Kihuma G, Atibu J, Thwai KL, Svec WM, Goel V, Nseka T, Lin JT, Bailey JA, Emch M, Carrel M, Juliano JJ, Tshefu A, Parr JB. Epidemiology of Plasmodium malariae and Plasmodium ovale spp. in Kinshasa Province, Democratic Republic of Congo. Nat Commun 2023; 14:6618. [PMID: 37857597 PMCID: PMC10587068 DOI: 10.1038/s41467-023-42190-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 10/03/2023] [Indexed: 10/21/2023] Open
Abstract
Reports suggest non-falciparum species are an underappreciated cause of malaria in sub-Saharan Africa but their epidemiology is ill-defined, particularly in highly malaria-endemic regions. We estimated incidence and prevalence of PCR-confirmed non-falciparum and Plasmodium falciparum malaria infections within a longitudinal study conducted in Kinshasa, Democratic Republic of Congo (DRC) between 2015-2017. Children and adults were sampled at biannual household surveys and routine clinic visits. Among 9,089 samples from 1,565 participants, incidences of P. malariae, P. ovale spp., and P. falciparum infections by 1-year were 7.8% (95% CI: 6.4%-9.1%), 4.8% (95% CI: 3.7%-5.9%) and 57.5% (95% CI: 54.4%-60.5%), respectively. Non-falciparum prevalences were higher in school-age children, rural and peri-urban sites, and P. falciparum co-infections. P. falciparum remains the primary driver of malaria in the DRC, though non-falciparum species also pose an infection risk. As P. falciparum interventions gain traction in high-burden settings, continued surveillance and improved understanding of non-falciparum infections are warranted.
Collapse
Affiliation(s)
- Rachel Sendor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| | - Kristin Banek
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Melchior M Kashamuka
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Nono Mvuama
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Joseph A Bala
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Marthe Nkalani
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Georges Kihuma
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Joseph Atibu
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Kyaw L Thwai
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - W Matthew Svec
- University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Varun Goel
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Carolina Population Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Tommy Nseka
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Jessica T Lin
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Jeffrey A Bailey
- Department of Pathology and Laboratory Medicine and Center for Computational Molecular Biology, Brown University, Providence, RI, USA
| | - Michael Emch
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Margaret Carrel
- Department of Geographical and Sustainability Sciences, University of Iowa, Iowa City, IA, USA
| | - Jonathan J Juliano
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Antoinette Tshefu
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Jonathan B Parr
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA.
| |
Collapse
|
6
|
Stanley CC, Chirombo J, Msuku H, Phiri VS, Patson N, Kazembe LN, Chinkhumba J, Kapito-Tembo A, Mathanga DP. Prompt treatment-seeking behaviour varies within communities among guardians of children with malaria-related fever in Malawi. Malar J 2023; 22:246. [PMID: 37633902 PMCID: PMC10463323 DOI: 10.1186/s12936-023-04680-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 08/18/2023] [Indexed: 08/28/2023] Open
Abstract
BACKGROUND In Malawi, malaria is responsible for 40% of hospital deaths. Prompt diagnosis and effective treatment within 24 h of fever onset is critical to prevent progression from uncomplicated to severe disease and to reduce transmission. METHODS As part of the large evaluation of the malaria vaccine implementation programme (MVIP), this study analysed survey data to investigate whether prompt treatment-seeking behaviour is clustered at community-level according to socio-economic demographics. RESULTS From 4563 households included in the survey, 4856 children aged 5-48 months were enrolled. Out of 4732 children with documented gender, 52.2% were female and 47.8% male. Among the 4856 children, 33.8% reported fever in the two weeks prior to the survey. Fever prevalence was high in communities with low socio-economic status (SES) (38.3% [95% CI: 33.7-43.5%]) and low in areas with high SES (29.8% [95% CI: 25.6-34.2%]). Among children with fever, 648 (39.5%) sought treatment promptly i.e., within 24 h from onset of fever symptoms. Children were more likely to be taken for prompt treatment among guardians with secondary education compared to those without formal education (aOR:1.37, 95% CI: 1.11-3.03); in communities with high compared to low SES [aOR: 2.78, 95% CI: 1.27-6.07]. Children were less likely to be taken for prompt treatment if were in communities far beyond 5 km to health facility than within 5 km [aOR: 0.44, 95% CI: 0.21-0.92]. CONCLUSION The high heterogeneity in prevalence of fever and levels of prompt treatment-seeking behaviour underscore the need to promote community-level malaria control interventions (such as use of long-lasting insecticide-treated nets (LLINs), indoor residual spraying (IRS), intermittent preventive therapy (IPT), presumptive treatment and education). Programmes aimed at improving treatment-seeking behaviour should consider targeting communities with low SES and those far from health facility.
Collapse
Affiliation(s)
- Christopher C Stanley
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Chichiri, Private Bag 360, Blantyre, Malawi.
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi.
| | - James Chirombo
- Malawi-Liverpool-Wellcome Clinical Research Programme, Blantyre, Malawi
| | - Harrison Msuku
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Chichiri, Private Bag 360, Blantyre, Malawi
| | - Vincent S Phiri
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Noel Patson
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Chichiri, Private Bag 360, Blantyre, Malawi
| | - Lawrence N Kazembe
- Department of Computing, Mathematical and Statistical Sciences, University of Namibia, Windhoek, Namibia
| | - Jobiba Chinkhumba
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Chichiri, Private Bag 360, Blantyre, Malawi
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Atupele Kapito-Tembo
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Chichiri, Private Bag 360, Blantyre, Malawi
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Don P Mathanga
- MAC-Communicable Diseases Action Centre, Kamuzu University of Health Sciences, Chichiri, Private Bag 360, Blantyre, Malawi
- School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi
| |
Collapse
|
7
|
Sendor R, Mitchell CL, Chacky F, Mohamed A, Mhamilawa LE, Molteni F, Nyinondi S, Kabula B, Mkali H, Reaves EJ, Serbantez N, Kitojo C, Makene T, Kyaw T, Muller M, Mwanza A, Eckert EL, Parr JB, Lin JT, Juliano JJ, Ngasala B. Similar Prevalence of Plasmodium falciparum and Non-P. falciparum Malaria Infections among Schoolchildren, Tanzania 1. Emerg Infect Dis 2023; 29:1143-1153. [PMID: 37209670 DOI: 10.3201/eid2906.221016] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023] Open
Abstract
Achieving malaria elimination requires considering both Plasmodium falciparum and non-P. falciparum infections. We determined prevalence and geographic distribution of 4 Plasmodium spp. by performing PCR on dried blood spots collected within 8 regions of Tanzania during 2017. Among 3,456 schoolchildren, 22% had P. falciparum, 24% had P. ovale spp., 4% had P. malariae, and 0.3% had P. vivax infections. Most (91%) schoolchildren with P. ovale infections had low parasite densities; 64% of P. ovale infections were single-species infections, and 35% of those were detected in low malaria endemic regions. P. malariae infections were predominantly (73%) co-infections with P. falciparum. P. vivax was detected mostly in northern and eastern regions. Co-infections with >1 non-P. falciparum species occurred in 43% of P. falciparum infections. A high prevalence of P. ovale infections exists among schoolchildren in Tanzania, underscoring the need for detection and treatment strategies that target non-P. falciparum species.
Collapse
|
8
|
Sendor R, Banek K, Kashamuka MM, Mvuama N, Bala JA, Nkalani M, Kihuma G, Atibu J, Thwai KL, Svec WM, Goel V, Nseka T, Lin JT, Bailey JA, Emch M, Carrel M, Juliano JJ, Tshefu A, Parr JB. Epidemiology of Plasmodium malariae and Plasmodium ovale spp. in a highly malaria-endemic country: a longitudinal cohort study in Kinshasa Province, Democratic Republic of Congo. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.04.20.23288826. [PMID: 37790376 PMCID: PMC10543032 DOI: 10.1101/2023.04.20.23288826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Background Increasing reports suggest that non-falciparum species are an underappreciated cause of malaria in sub-Saharan Africa, but their epidemiology is not well-defined. This is particularly true in regions of high P. falciparum endemicity such as the Democratic Republic of Congo (DRC), where 12% of the world's malaria cases and 13% of deaths occur. Methods and Findings The cumulative incidence and prevalence of P. malariae and P. ovale spp. infection detected by real-time PCR were estimated among children and adults within a longitudinal study conducted in seven rural, peri-urban, and urban sites from 2015-2017 in Kinshasa Province, DRC. Participants were sampled at biannual household survey visits (asymptomatic) and during routine health facility visits (symptomatic). Participant-level characteristics associated with non-falciparum infections were estimated for single- and mixed-species infections. Among 9,089 samples collected from 1,565 participants over a 3-year period, the incidence of P. malariae and P. ovale spp. infection was 11% (95% CI: 9%-12%) and 7% (95% CI: 5%-8%) by one year, respectively, compared to a 67% (95% CI: 64%-70%) one-year cumulative incidence of P. falciparum infection. Incidence continued to rise in the second year of follow-up, reaching 26% and 15% in school-age children (5-14yo) for P. malariae and P. ovale spp., respectively. Prevalence of P. malariae, P. ovale spp., and P. falciparum infections during household visits were 3% (95% CI: 3%-4%), 1% (95% CI: 1%-2%), and 35% (95% CI: 33%-36%), respectively. Non-falciparum malaria was more prevalent in rural and peri-urban vs. urban sites, in school-age children, and among those with P. falciparum co-infection. A crude association was detected between P. malariae and any anemia in the symptomatic clinic population, although this association did not hold when stratified by anemia severity. No crude associations were detected between non-falciparum infection and fever prevalence. Conclusions P. falciparum remains the primary driver of malaria morbidity and mortality in the DRC. However, non-falciparum species also pose an infection risk across sites of varying urbanicity and malaria endemicity within Kinshasa, DRC, particularly among children under 15 years of age. As P. falciparum interventions gain traction in high-burden settings like the DRC, continued surveillance and improved understanding of non-falciparum infections are warranted.
Collapse
Affiliation(s)
- Rachel Sendor
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Kristin Banek
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | | | - Nono Mvuama
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Joseph A. Bala
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Marthe Nkalani
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Georges Kihuma
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Joseph Atibu
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Kyaw L. Thwai
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - W. Matthew Svec
- University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Varun Goel
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Tommy Nseka
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Jessica T. Lin
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Jeffrey A. Bailey
- Department of Pathology and Laboratory Medicine and Center for Computational Molecular Biology, Brown University, Providence, Rhode Island, United States of America
| | - Michael Emch
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Department of Geography, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Margaret Carrel
- Department of Geographical and Sustainability Sciences, University of Iowa, Iowa City, Iowa, United States of America
| | - Jonathan J. Juliano
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Antoinette Tshefu
- Ecole de Santé Publique, Faculté de Médecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Jonathan B. Parr
- Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| |
Collapse
|
9
|
John CC. What Can Twins Teach Us About Malaria Epidemiology? J Infect Dis 2023; 227:169-170. [PMID: 35849705 DOI: 10.1093/infdis/jiac297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Accepted: 07/11/2022] [Indexed: 01/14/2023] Open
Affiliation(s)
- Chandy C John
- Ryan White Center for Pediatric Infectious Diseases and Global Health, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| |
Collapse
|
10
|
Kayange M, M'baya B, Hwandih T, Saker J, Coetzer TL, Münster M. Automated measurement of malaria parasitaemia among asymptomatic blood donors in Malawi using the Sysmex XN-31 analyser: could such data be used to complement national malaria surveillance in real time? Malar J 2022; 21:299. [PMID: 36284305 DOI: 10.1186/s12936-022-04314-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 10/05/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The recent worldwide increase in malaria cases highlights the need for renewed efforts to eliminate malaria. The World Health Organization advocates that malaria surveillance becomes a core intervention. Current methods to estimate the malaria burden rely on clinical malaria case reports and surveys of asymptomatic parasite infection mainly from children < 5 years. In this study the hypothesis was that screening blood donors for malaria parasites would provide real-time information on the asymptomatic reservoir of parasites in the adult population and mirror other surveillance data. METHODS This study was conducted in Malawi, a high malaria burden country, at the Malawi Blood Transfusion Service, which collects blood units at donation sites countrywide. A secondary analysis was conducted on data obtained from a prior Sysmex XN-31 analyser malaria diagnostic evaluation study utilizing residual donor blood samples. XN-31 malaria results, donor age, sex, geographical location, and collection date, were analysed using standard statistical methods. RESULTS The malaria parasite prevalence in blood donors was 11.6% (614/5281 samples) increasing seasonally from December (8.6%) to April (18.3%). The median age was 21 years and 45.9% of donors were from urban areas, which showed a lower prevalence compared to non-urban regions. The Central administrative region had the highest and the Northern region the lowest malaria parasite prevalence. The donors were predominantly male (80.2%), 13.1% of whom had malaria parasites, which was significantly higher (p < 0.0001) than for female donors (7.4%). Multivariable logistic regression analysis showed that age, location, and collection month were significant predictors of malaria positivity in males, whereas in females only location was significant. There was no gender difference in parasite density nor gametocyte carriage. CONCLUSIONS This study demonstrates the powerful utility of screening blood donors for malaria parasites using the XN-31, which not only improves the safety of blood transfusion, but provides valuable complementary surveillance data for malaria control, especially targeting males, who are generally excluded from periodic household surveys. Blood donations are sourced countrywide, year-round, and thus provide dynamic, real-time information on the malaria burden. Furthermore, the XN-31 identifies the asymptomatic human reservoir of infectious gametocytes, which must be targeted to eliminate malaria.
Collapse
Affiliation(s)
- Michael Kayange
- National Malaria Control Programme, Ministry of Health, Lilongwe, Malawi
| | | | - Talent Hwandih
- Sysmex Europe SE, Bornbarch 1, 22848, Norderstedt, Germany
| | - Jarob Saker
- Sysmex Europe SE, Bornbarch 1, 22848, Norderstedt, Germany
| | - Thérèsa L Coetzer
- Sysmex Europe SE, Bornbarch 1, 22848, Norderstedt, Germany.,Faculty of Health Sciences, Wits Research Institute for Malaria, University of the Witwatersrand, Johannesburg, South Africa
| | - Marion Münster
- Sysmex Europe SE, Bornbarch 1, 22848, Norderstedt, Germany.
| |
Collapse
|
11
|
Mandala W, Munyenyembe A, Sulani I, Soko M, Mallewa J, Hiestand J. Acute Malaria in Malawian Children and Adults is Characterized by Thrombocytopenia That Normalizes in Convalescence. J Blood Med 2022; 13:485-494. [PMID: 36092852 PMCID: PMC9462550 DOI: 10.2147/jbm.s376476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 08/23/2022] [Indexed: 11/23/2022] Open
Abstract
Background Plasmodium falciparum malaria has been linked with significant perturbations of the peripheral cell-mediated immune system during acute phase. Some of these changes include lower than normal platelet counts. Although the exact mechanisms that drive thrombocytopenia in P. falciparum malaria are not fully known, a number of hypotheses have been proposed. We conducted two sets of studies with one aimed at determining platelet counts in Malawian children, and the other in adults during acute P. falciparum malaria and a month post treatment. Materials and Methods We recruited a total of 113 HIV-uninfected children with acute malaria [n=54 with uncomplicated malaria (UCM), n=30 with severe malarial anemia (SMA), n=29 presenting with cerebral malaria (CM)]. We also recruited 42 HIV-uninfected healthy controls. Out of the 113 participants with malaria, 73 (65%) [n=34 (63%) UCM, n=21 (70%) SMA and n=18 (62%) CM] were successfully followed-up one month after treatment. A 5mL peripheral blood sample was collected for platelet count using HMX Haematological Analyzer analysis both at baseline (acute malaria) and at follow-up a month later. Platelet counts were also determined in blood samples of 106 HIV-uninfected adults, 47 of whom presented with UCM and 29 with severe malaria (SM) and these counts were compared to those of 30 healthy controls. Of the malaria cases, platelet counts for 44 UCM and 21 SM were determined again during follow-up a month after treatment. Results In both children and adults, platelet counts were significantly lower during acute disease compared to the levels in the healthy controls with the lowest levels observed in CM (children) or SM (adults). These lower than normal levels increased close to normal levels a month post treatment. Conclusion P. falciparum malaria in Malawian children and adults was characterized by profound thrombocytopenia which recovered during convalescence.
Collapse
Affiliation(s)
- Wilson Mandala
- Basic Sciences Department, Kamuzu University of Health Sciences, Blantyre, Malawi.,Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,Academy of Medical Sciences, Malawi University of Science and Technology, Thyolo, Malawi
| | - Alinane Munyenyembe
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Innocent Sulani
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Monica Soko
- Malawi Liverpool Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Jane Mallewa
- Medicine Department, Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Jasmin Hiestand
- Medicine Department, Kamuzu University of Health Sciences, Blantyre, Malawi
| |
Collapse
|