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Abossie A, Demissew A, Getachew H, Tsegaye A, Degefa T, Habtamu K, Zhong D, Wang X, Lee MC, Zhou G, King CL, Kazura JW, Yan G, Yewhalaw D. Higher outdoor mosquito density and Plasmodium infection rates in and around malaria index case households in low transmission settings of Ethiopia: Implications for vector control. Parasit Vectors 2024; 17:53. [PMID: 38321572 PMCID: PMC10848356 DOI: 10.1186/s13071-023-06088-2] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 12/07/2023] [Indexed: 02/08/2024] Open
Abstract
BACKGROUND Understanding the clustering of infections for persistent malaria transmission is critical to determining how and where to target specific interventions. This study aimed to determine the density, blood meal sources and malaria transmission risk of anopheline vectors by targeting malaria index cases, their neighboring households and control villages in Arjo-Didessa, southwestern Ethiopia. METHODS An entomological study was conducted concurrently with a reactive case detection (RCD) study from November 2019 to October 2021 in Arjo Didessa and the surrounding vicinity, southwestern Ethiopia. Anopheline mosquitoes were collected indoors and outdoors in index case households and their surrounding households (neighboring households), as well as in control households, using pyrethrum spray cache (PSC) and U.S. Centers for Disease Control and Prevention (CDC) light traps. Adult mosquitoes were morphologically identified, and speciation in the Anopheles gambiae complex was done by PCR. Mosquito Plasmodium infections and host blood meal sources were detected by circumsporozoite protein enzyme-linked immunosorbent assay (CSP-ELISA) and cytochrome b-based blood meal PCR, respectively. RESULTS Among the 770 anopheline mosquitoes collected, An. gambiae sensu lato (A. gambiae s.l.) was the predominant species, accounting for 87.1% (n = 671/770) of the catch, followed by the Anopheles coustani complex and Anopheles pharoensis, which accounted for 12.6% (n = 97/770) and 0.26% (n = 2/770) of the catch, respectively. From the sub-samples of An. gambiae s.l.analyzed with PCR, An. arabiensis and Anopheles amharicus were identified. The overall mean density of mosquitoes was 1.26 mosquitoes per trap per night using the CDC light traps. Outdoor mosquito density was significantly higher than indoor mosquito density in the index and neighboring households (P = 0.0001). The human blood index (HBI) and bovine blood index (BBI) of An. arabiensis were 20.8% (n = 34/168) and 24.0% (n = 41/168), respectively. The overall Plasmodium sporozoite infection rate of anophelines (An. arabiensis and An. coustani complex) was 4.4% (n = 34/770). Sporozoites were detected indoors and outdoors in captured anopheline mosquitoes. Of these CSP-positive species for Pv-210, Pv-247 and Pf, 41.1% (n = 14/34) were captured outdoors. A significantly higher proportion of sporozoite-infected mosquitoes were caught in index case households (5.6%, n = 8/141) compared to control households (1.1%, n = 2/181) (P = 0.02), and in neighboring households (5.3%, n = 24/448) compared to control households (P = 0.01). CONCLUSIONS The findings of this study indicated that malaria index cases and their neighboring households had higher outdoor mosquito densities and Plasmodium infection rates. The study also highlighted a relatively higher outdoor mosquito density, which could increase the potential risk of outdoor malaria transmission and may play a role in residual malaria transmission. Thus, it is important to strengthen the implementation of vector control interventions, such as targeted indoor residual spraying, long-lasting insecticidal nets and other supplementary vector control measures such as larval source management and community engagement approaches. Furthermore, in low transmission settings, such as the Arjo Didessa Sugarcane Plantation, providing health education to local communities, enhanced environmental management and entomological surveillance, along with case detection and management by targeting of malaria index cases and their immediate neighboring households, could be important measures to control residual malaria transmission and achieve the targeted elimination goals.
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Affiliation(s)
- Ashenafi Abossie
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia.
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia.
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia.
| | - Assalif Demissew
- Department of Medical Laboratory Sciences, College of Medicine and Health Sciences, Ambo University, Ambo, Ethiopia
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Hallelujah Getachew
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Department of Medical Laboratory Technology, Arba Minch College of Health Sciences, Arba Minch, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Arega Tsegaye
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Department of Biology, College of Natural Science, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Teshome Degefa
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
| | - Kassahun Habtamu
- Menelik II College of Health Sciences, Addis Ababa, Ethiopia
- Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Daibin Zhong
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Xiaoming Wang
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Ming-Chieh Lee
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Guofa Zhou
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Christopher L King
- Center for Global Health & Diseases, School of Medicine, Case Western Reserve University, Cleveland, 44106 OH, USA
| | - James W Kazura
- Center for Global Health & Diseases, School of Medicine, Case Western Reserve University, Cleveland, 44106 OH, USA
| | - Guiyun Yan
- Program in Public Health, University of California at Irvine, Irvine, CA, 92697, USA
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
- Tropical and Infectious Diseases Research Center (TIDRC), Jimma University, Jimma, Ethiopia
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Aidoo EK, Aboagye FT, Agginie GE, Botchway FA, Osei-Adjei G, Appiah M, Takyi RD, Sakyi SA, Amoah L, Arthur G, Lawson BW, Asmah RH, Boateng P, Ansah O, Krogfelt KA. Malaria elimination in Ghana: recommendations for reactive case detection strategy implementation in a low endemic area of Asutsuare, Ghana. Malar J 2024; 23:5. [PMID: 38167067 PMCID: PMC10759473 DOI: 10.1186/s12936-023-04792-z] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 11/15/2023] [Indexed: 01/05/2024] Open
Abstract
BACKGROUND Progress toward malaria elimination is increasing as many countries near zero indigenous malaria cases. In settings nearing elimination, interventions will be most effective at interrupting transmission when targeted at the residual foci of transmission. These foci may be missed due to asymptomatic infections. To solve this problem, the World Health Organization recommends reactive case detection (RACD). This case study was conducted to identify individuals with asymptomatic malaria, their predisposing risk factors and recommend RACD in Asutsuare, Ghana based on literature review and a cross sectional study. METHODS The study involved a search on PubMed and Google Scholar of literature published between 1st January, 2009-14th August, 2023 using the search terms "malaria" in "Asutsuare". Furthermore, structured questionnaires were administered to one hundred individuals without symptoms of malaria and screened using rapid diagnostic test (RDT) kits, microscopy and real-time polymerase chain reaction (rt-PCR). Malaria prevalence based on the three diagnostic techniques as well as potential malaria risk factors were assessed through questionnaires in a cross-sectional study. RESULTS Cumulatively, sixty-four (64) studies (Google Scholar, 57 and PubMed, 7) were reviewed and 22 studies included in the literature on malaria in Asutsuare, Ghana. Significant risk factors were occupation, distance from a house to a waterbody, age group and educational level. Out of the 100 samples, 3 (3%) were positive by RDT, 6 (6%) by microscopy and 9 (9%) by rt-PCR. Ages 5-14.9 years had the highest mean malaria parasite densities of 560 parasites/µl with Plasmodium falciparum as the dominant species in 4 participants. Moreover, in the age group ≥ 15, 2 participants (1 each) harboured P. falciparum and Plasmodium malariae parasites. RDT had a higher sensitivity (76.54%; CI95 66.82-85.54) than rt-PCR (33.33%; CI95 4.33-77.72), while both rt-PCR and RDT were observed to have a higher specificity (92.55; CI95 85.26-96.95) and (97.30; CI95 93.87-99.13), respectively in the diagnosis of malaria. CONCLUSION In Asutsuare, Ghana, a low endemic area, the elimination of malaria may require finding individuals with asymptomatic infections. Given the low prevalence of asymptomatic individuals identified in this study and as repleted in the literature review, which favours RACD, Asutsuare is a possible setting receptive for RACD implementation.
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Affiliation(s)
| | - Frank Twum Aboagye
- Bio-Medical and Public Health Research Unit, Council for Scientific and Industrial Research - Water Research Institute, Accra, Ghana
| | - George Edem Agginie
- Department of Medical Laboratory Technology, Accra Technical University, Accra, Ghana
| | - Felix Abekah Botchway
- Department of Medical Laboratory Technology, Accra Technical University, Accra, Ghana
| | - George Osei-Adjei
- Department of Medical Laboratory Technology, Accra Technical University, Accra, Ghana
| | - Michael Appiah
- Department of Medical Laboratory Technology, Accra Technical University, Accra, Ghana
| | - Ruth Duku Takyi
- Department of Medical Laboratory Technology, Accra Technical University, Accra, Ghana
| | - Samuel Asamoah Sakyi
- Department of Molecular Medicine, Kwame Nkrumah University of Science & Technology, University Post Office, Kumasi, Ghana
| | - Linda Amoah
- Department of Immunology, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - George Arthur
- Department of Medical Laboratory, Accra Psychiatric Hospital, Accra, Ghana
| | - Bernard Walter Lawson
- Department of Theoretical & Applied Biology, Kwame Nkrumah University of Science & Technology, University Post Office, Kumasi, Ghana
| | - Richard Harry Asmah
- Department of Biomedical Sciences, School of Basic and Biomedical Science, University of Health & Allied Sciences, Ho, Ghana
| | - Paul Boateng
- National Malaria Elimination Programme, Accra, Ghana
| | - Otubea Ansah
- National Malaria Elimination Programme, Accra, Ghana
| | - Karen Angeliki Krogfelt
- Department of Science and Environment, Unit of Molecular and Medical Biology, The PandemiX Center, Roskilde University, 4000, Roskilde, Denmark
- Department of Virus and Microbiological Special Diagnostics, Statens Serum Institut, 2300, Copenhagen, Denmark
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Win Han Oo, Nguyen XT, Ngo TVA, Ngo DT, Win Htike, Aye Tun N, Kaung Myat Thu, Cutts J, Nguyen THP, May Chan Oo, Ei Phyu Htwe, Aung Khine Zaw, O'Flaherty K, Agius PA, Fowkes FJI. Performance and feasibility of reactive surveillance and response strategies for malaria elimination in Vietnam: a mixed-methods study. Malar J 2023; 22:229. [PMID: 37545009 PMCID: PMC10405448 DOI: 10.1186/s12936-023-04660-w] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 07/27/2023] [Indexed: 08/08/2023] Open
Abstract
BACKGROUND To enhance malaria elimination, Vietnam adopted a Reactive Surveillance and Response (RASR) Strategy in which malaria case notification and investigation must be completed within 2 days followed by a focus investigation within 7 days. The nationwide performance of Vietnam's RASR strategy has yet to be evaluated. This study aims to evaluate the performance and feasibility of RASR in Vietnam, thereby providing recommendations for improved RASR. METHODS To assess malaria RASR in Vietnam, a mixed-methods study of (1) secondary data analysis of nationwide malaria case-based dataset from 2017 to 2021; (2) a quantitative survey, and (3) qualitative in-depth interviews and focus group discussions administered to central, provincial and district level stakeholders/staff and to the commune and community level front line health services providers was conducted. RESULTS In Vietnam, there are guidelines and procedures for implementation of each step of RASR. The completeness of case notification on the reported monthly aggregated data was very high in both the paper-based (12,463/12,498, 99.7% in 2017-2020) and electronic reporting systems (467/467, 100% in 2021 when electronic reporting was introduced); however, there were delays in notification while using the paper-based system (timely notification-7,978/12,498, 63.8%). In 2021, the completeness (453/467, 97.0%) and timeliness (371/467, 79.4%) of case investigation were found to be high. Reactive case detection was the major focus investigation response, with fever screening achievement of 88.6% (11,481 / 12,965) and 88.5% (11,471 / 12,965) among index case and neighbouring household members, respectively. CONCLUSIONS Overall, there was policy commitment for implementation of RASR in Vietnam. The completeness and timeliness of case notification and case investigation were high and improved after the introduction of the electronic reporting system. More evidence is required for reactive case detection in defining the screening area or population.
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Affiliation(s)
- Win Han Oo
- Disease Elimination Programme, Burnet Institute, 85 Commercial Rd, Melbourne, VIC, Australia.
- Health Security Programme, Burnet Institute Myanmar, 226 U Wisara Road, Yangon, Myanmar.
| | - Xuan Thang Nguyen
- Department of Epidemiology, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | | | - Duc Thang Ngo
- Department of Epidemiology, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - Win Htike
- Health Security Programme, Burnet Institute Myanmar, 226 U Wisara Road, Yangon, Myanmar
| | - Nilar Aye Tun
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, VIC, Australia
| | - Kaung Myat Thu
- Health Security Programme, Burnet Institute Myanmar, 226 U Wisara Road, Yangon, Myanmar
| | - Julia Cutts
- Disease Elimination Programme, Burnet Institute, 85 Commercial Rd, Melbourne, VIC, Australia
| | - T Hong Phuc Nguyen
- Department of Epidemiology, National Institute of Malariology, Parasitology and Entomology, Hanoi, Vietnam
| | - May Chan Oo
- Health Security Programme, Burnet Institute Myanmar, 226 U Wisara Road, Yangon, Myanmar
| | - Ei Phyu Htwe
- Health Security Programme, Burnet Institute Myanmar, 226 U Wisara Road, Yangon, Myanmar
| | - Aung Khine Zaw
- Health Security Programme, Burnet Institute Myanmar, 226 U Wisara Road, Yangon, Myanmar
| | - Katherine O'Flaherty
- Disease Elimination Programme, Burnet Institute, 85 Commercial Rd, Melbourne, VIC, Australia
| | - Paul A Agius
- Disease Elimination Programme, Burnet Institute, 85 Commercial Rd, Melbourne, VIC, Australia
- Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, VIC, Australia
| | - Freya J I Fowkes
- Disease Elimination Programme, Burnet Institute, 85 Commercial Rd, Melbourne, VIC, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, VIC, Australia
- Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, VIC, Australia
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Das AM, Hetzel MW, Yukich JO, Stuck L, Fakih BS, Al-mafazy AWH, Ali A, Chitnis N. The impact of reactive case detection on malaria transmission in Zanzibar in the presence of human mobility. Epidemics 2022; 41:100639. [PMID: 36343496 PMCID: PMC9758615 DOI: 10.1016/j.epidem.2022.100639] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 09/02/2022] [Accepted: 10/03/2022] [Indexed: 12/29/2022] Open
Abstract
Malaria persists at low levels on Zanzibar despite the use of vector control and case management. We use a metapopulation model to investigate the role of human mobility in malaria persistence on Zanzibar, and the impact of reactive case detection. The model was parameterized using survey data on malaria prevalence, reactive case detection, and travel history. We find that in the absence of imported cases from mainland Tanzania, malaria would likely cease to persist on Zanzibar. We also investigate potential intervention scenarios that may lead to elimination, especially through changes to reactive case detection. While we find that some additional cases are removed by reactive case detection, a large proportion of cases are missed due to many infections having a low parasite density that go undetected by rapid diagnostic tests, a low rate of those infected with malaria seeking treatment, and a low rate of follow up at the household level of malaria cases detected at health facilities. While improvements in reactive case detection would lead to a reduction in malaria prevalence, none of the intervention scenarios tested here were sufficient to reach elimination. Imported cases need to be treated to have a substantial impact on prevalence.
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Affiliation(s)
- Aatreyee M. Das
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland,University of Basel, Basel, Switzerland,Corresponding author at: Swiss Tropical and Public Health Institute, Allschwil, Switzerland.
| | - Manuel W. Hetzel
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland,University of Basel, Basel, Switzerland
| | - Joshua O. Yukich
- Center for Applied Malaria Research and Evaluation, Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA
| | - Logan Stuck
- Center for Applied Malaria Research and Evaluation, Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA
| | - Bakar S. Fakih
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland,University of Basel, Basel, Switzerland,Ifakara Health Institute, Dar es Salaam, United Republic of Tanzania
| | | | - Abdullah Ali
- Zanzibar Malaria Elimination Programme, Zanzibar, United Republic of Tanzania
| | - Nakul Chitnis
- Swiss Tropical and Public Health Institute, Allschwil, Switzerland,University of Basel, Basel, Switzerland
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Abdelmenan S, Teka H, Hwang J, Girma S, Chibsa S, Tongren E, Murphy M, Haile M, Dillu D, Kassim J, Behaksra S, Tadesse FG, Yukich J, Berhane Y, Worku A, Keating J, Zewde A, Gadisa E. Evaluation of the effect of targeted Mass Drug Administration and Reactive Case Detection on malaria transmission and elimination in Eastern Hararghe zone, Oromia, Ethiopia: a cluster randomized control trial. Trials 2022; 23:267. [PMID: 35392979 PMCID: PMC8989114 DOI: 10.1186/s13063-022-06199-8] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 03/25/2022] [Indexed: 11/30/2022] Open
Abstract
Background Reactive and proactive case detection measures are widely implemented by national malaria elimination programs globally. Ethiopia decided to include Reactive Case Detection (RCD) and targeted Mass Drug Administration (tMDA) approaches as part of their elimination strategy along with rigorous evaluation. The purpose of this study is to compare the impact of RCD and tMDA on malaria elimination over the 2-year study period, by looking at the annual parasite incidence before and after the intervention. Methods The study will be conducted in the East Hararghe zone of Ethiopia. Malaria transmission in the area is low to moderate. This study will deploy a community-based, three-arm, cluster-randomized control trial implemented over 2 years. Forty-eight clusters (16 clusters per arm) will be selected based on the annual number of confirmed malaria cases seen in the cluster. All clusters will receive the current standard of care in terms of malaria elimination interventions provided by the national malaria control program. In addition, following the identification of malaria parasite infection, individuals who reside within a 100-m radius of the index case will receive a diagnosis for malaria and treatment if positive in the RCD arm or presumptive treatment in the tMDA arm. The primary effectiveness endpoint will be measured at baseline and endline for each intervention arm and compared to the control arm using a difference in difference approach. Discussion This randomized controlled trial will provide evidence of the impact of the proposed intervention approaches for malaria elimination. Trial registration ClinicalTrials.gov NCT04241705. Registration date: January 27, 2020.
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Affiliation(s)
- Semira Abdelmenan
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia.
| | - Hiwot Teka
- U.S. President's Malaria Initiative, Addis Ababa, Ethiopia
| | - Jimee Hwang
- U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Samuel Girma
- U.S. President's Malaria Initiative, Addis Ababa, Ethiopia
| | - Sheleme Chibsa
- U.S. President's Malaria Initiative, Addis Ababa, Ethiopia
| | - Eric Tongren
- U.S. Centers for Disease Control and Prevention, Addis Ababa, Ethiopia
| | - Matthew Murphy
- U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA
| | | | | | - Jawar Kassim
- Oromia Regional Health Bureau, Addis Ababa, Ethiopia
| | | | | | | | - Yemane Berhane
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
| | - Alemayehu Worku
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
| | | | - Ayele Zewde
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
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Roberts KW, Smith Gueye C, Baltzell K, Ntuku H, McCreesh P, Maglior A, Whittemore B, Uusiku P, Mumbengegwi D, Kleinschmidt I, Gosling R, Hsiang MS. Community acceptance of reactive focal mass drug administration and reactive focal vector control using indoor residual spraying, a mixed-methods study in Zambezi region, Namibia. Malar J 2021; 20:162. [PMID: 33752673 PMCID: PMC7986500 DOI: 10.1186/s12936-021-03679-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 03/01/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In Namibia, as in many malaria elimination settings, reactive case detection (RACD), or malaria testing and treatment around index cases, is a standard intervention. Reactive focal mass drug administration (rfMDA), or treatment without testing, and reactive focal vector control (RAVC) in the form of indoor residual spraying, are alternative or adjunctive interventions, but there are limited data regarding their community acceptability. METHODS A parent trial aimed to compare the effectiveness of rfMDA versus RACD, RAVC versus no RAVC, and rfMDA + RAVC versus RACD only. To assess acceptability of these interventions, a mixed-methods study was conducted using key informant interviews (KIIs) and focus group discussions (FGDs) in three rounds (pre-trial and in years 1 and 2 of the trial), and an endline survey. RESULTS In total, 17 KIIs, 49 FGDs were conducted with 449 people over three annual rounds of qualitative data collection. Pre-trial, community members more accurately predicted the level of community acceptability than key stakeholders. Throughout the trial, key participant motivators included: malaria risk perception, access to free community-based healthcare and IRS, and community education by respectful study teams. RACD or rfMDA were offered to 1372 and 8948 individuals in years 1 and 2, respectively, and refusal rates were low (< 2%). RAVC was offered to few households (n = 72) in year 1. In year 2, RAVC was offered to more households (n = 944) and refusals were < 1%. In the endline survey, 94.3% of 2147 respondents said they would participate in the same intervention again. CONCLUSIONS Communities found both reactive focal interventions and their combination highly acceptable. Engaging communities and centering and incorporating their perspectives and experiences during design, implementation, and evaluation of this community-based intervention was critical for optimizing study engagement.
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Affiliation(s)
- Kathryn W Roberts
- Malaria Elimination Initiative, Global Health Group, University of California, (UCSF), 550 16th St, San Francisco, CA, USA.
- Global Programs for Research and Training, Malaria Elimination Initiative Namibia, Windhoek, Namibia.
| | - Cara Smith Gueye
- Malaria Elimination Initiative, Global Health Group, University of California, (UCSF), 550 16th St, San Francisco, CA, USA
- Global Programs for Research and Training, Malaria Elimination Initiative Namibia, Windhoek, Namibia
| | - Kimberly Baltzell
- Malaria Elimination Initiative, Global Health Group, University of California, (UCSF), 550 16th St, San Francisco, CA, USA
- Department of Family Health Care Nursing, School of Nursing, UCSF, San Francisco, USA
| | - Henry Ntuku
- Malaria Elimination Initiative, Global Health Group, University of California, (UCSF), 550 16th St, San Francisco, CA, USA
- Global Programs for Research and Training, Malaria Elimination Initiative Namibia, Windhoek, Namibia
| | - Patrick McCreesh
- Department of Pediatrics, University of Texas, Southwestern Medical Center, 5323 Harry Hines Blvd, TX, Dallas, USA
| | - Alysse Maglior
- Malaria Elimination Initiative, Global Health Group, University of California, (UCSF), 550 16th St, San Francisco, CA, USA
| | - Brooke Whittemore
- Department of Pediatrics, University of Texas, Southwestern Medical Center, 5323 Harry Hines Blvd, TX, Dallas, USA
| | - Petrina Uusiku
- National Vectorborne Diseases Control Programme, Namibia Ministry of Health and Social Services, Windhoek, Namibia
| | - Davis Mumbengegwi
- Multidisciplinary Research Centre, University of Namibia, Windhoek, Namibia
| | - Immo Kleinschmidt
- Wits Research Institute for Malaria, Wits/SAMRC Collaborating Centre for Multi-Disciplinary Research on Malaria, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
- Southern Africa Development Community Malaria Elimination Eight Secretariat, Windhoek, Namibia
| | - Roly Gosling
- Malaria Elimination Initiative, Global Health Group, University of California, (UCSF), 550 16th St, San Francisco, CA, USA
- Global Programs for Research and Training, Malaria Elimination Initiative Namibia, Windhoek, Namibia
- Multidisciplinary Research Centre, University of Namibia, Windhoek, Namibia
| | - Michelle S Hsiang
- Malaria Elimination Initiative, Global Health Group, University of California, (UCSF), 550 16th St, San Francisco, CA, USA.
- Department of Pediatrics, University of Texas, Southwestern Medical Center, 5323 Harry Hines Blvd, TX, Dallas, USA.
- Department of Pediatrics, UCSF, San Francisco, USA.
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7
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Deen J, Mukaka M, von Seidlein L. What is the yield of malaria reactive case detection in the Greater Mekong Sub-region? A review of published data and meta-analysis. Malar J 2021; 20:131. [PMID: 33663484 PMCID: PMC7934542 DOI: 10.1186/s12936-021-03667-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [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: 10/11/2020] [Accepted: 02/24/2021] [Indexed: 01/01/2023] Open
Abstract
Background Reactive malaria case detection involves the screening of those in contact with index cases and is used in countries in the Greater Mekong Sub-region. The yield of reactive case detection, defined here as the percentage of positive malaria cases among potential contacts who were screened, was assessed. Methods A literature search was conducted on PubMed to identify studies on reactive case detection in the Greater Mekong Sub-region. Eligible published articles were reviewed and pooled estimates from the studies were calculated, by type of malaria test used. Results Eighty-five publications were retrieved, of which 8 (9.4%) eligible articles were included in the analysis. The yield from reactive case detection ranged from 0.1 to 4.2%, with higher rates from PCR testing compared with microscopy and/or rapid diagnostic test. The overall yield from microscopy and/or rapid diagnostic test was 0.56% (95% CI 0.31–0.88%), while that from PCR was 2.35% (95% CI 1.19–3.87%). The two studies comparing different target groups showed higher yield from co-workers/co-travellers, compared with household contacts. Conclusion In low malaria transmission settings, the effectiveness of reactive case detection is diminishing. In the Greater Mekong Sub-region, modifying reactive case detection from household contacts to co-workers/co-travellers and from testing to presumptive treatment of targeted contacts, could increase the impact of this approach.
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Affiliation(s)
- Jacqueline Deen
- Institute of Child Health and Human Development, National Institutes of Health, University of the Philippines, 623 P. Gil St, 1000, Manila, Philippines.
| | - Mavuto Mukaka
- Faculty of Tropical Medicine, Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Lorenz von Seidlein
- Faculty of Tropical Medicine, Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.,Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
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8
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Gunasekera WMKTDAW, Premaratne R, Fernando D, Munaz M, Piyasena MGY, Perera D, Wickremasinghe R, Ranaweera KDNP, Mendis K. A comparative analysis of the outcome of malaria case surveillance strategies in Sri Lanka in the prevention of re-establishment phase. Malar J 2021; 20:80. [PMID: 33563273 PMCID: PMC7871399 DOI: 10.1186/s12936-021-03621-5] [Citation(s) in RCA: 8] [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] [Received: 12/10/2020] [Revised: 02/02/2021] [Accepted: 02/03/2021] [Indexed: 11/30/2022] Open
Abstract
Background Sri Lanka sustained its malaria-free status by implementing, among other interventions, three core case detection strategies namely Passive Case Detection (PCD), Reactive Case Detection (RACD) and Proactive Case Detection (PACD). The outcomes of these strategies were analysed in terms of their effectiveness in detecting malaria infections for the period from 2017 to 2019. Methods Comparisons were made between the surveillance methods and between years, based on data obtained from the national malaria database and individual case reports of malaria patients. The number of blood smears examined microscopically was used as the measure of the volume of tests conducted. The yield from each case detection method was calculated as the proportion of blood smears which were positive for malaria. Within RACD and PACD, the yield of sub categories of travel cohorts and spatial cohorts was ascertained for 2019. Results A total of 158 malaria cases were reported in 2017–2019. During this period between 666,325 and 725,149 blood smears were examined annually. PCD detected 95.6 %, with a yield of 16.1 cases per 100,000 blood smears examined. RACD and PACD produced a yield of 11.2 and 0.3, respectively. The yield of screening the sub category of travel cohorts was very high for RACD and PACD being 806.5 and 44.9 malaria cases per 100,000 smears, respectively. Despite over half of the blood smears examined being obtained by screening spatial cohorts within RACD and PACD, the yield of both was zero over all three years. Conclusions The PCD arm of case surveillance is the most effective and, therefore, has to continue and be further strengthened as the mainstay of malaria surveillance. Focus on travel cohorts within RACD and PACD should be even greater. Screening of spatial cohorts, on a routine basis and solely because people are resident in previously malarious areas, may be wasteful, except in situations where the risk of local transmission is very high, or is imminent. These findings may apply more broadly to most countries in the post-elimination phase.
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Affiliation(s)
| | - Risintha Premaratne
- World Health Organization Regional Office for South-East Asia, New Delhi, India
| | - Deepika Fernando
- Department of Parasitology, Faculty of Medicine, University of Colombo, 25 Kynsey Road, Colombo, Sri Lanka
| | - Muzrif Munaz
- Anti Malaria Campaign, 555/5 Public Health Building, Narahenpita, Sri Lanka
| | - M G Y Piyasena
- Anti Malaria Campaign, 555/5 Public Health Building, Narahenpita, Sri Lanka
| | - Devika Perera
- Anti Malaria Campaign, 555/5 Public Health Building, Narahenpita, Sri Lanka
| | - Rajitha Wickremasinghe
- Department of Public Health, Faculty of Medicine, University of Kelaniya, P.O. Box 6, Thalagolla Road, 11010, Ragama, Sri Lanka
| | | | - Kamini Mendis
- Department of Parasitology, Faculty of Medicine, University of Colombo, 25 Kynsey Road, Colombo, Sri Lanka.
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9
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Perera R, Caldera A, Wickremasinghe AR. Reactive Case Detection (RACD) and foci investigation strategies in malaria control and elimination: a review. Malar J 2020; 19:401. [PMID: 33172462 PMCID: PMC7653886 DOI: 10.1186/s12936-020-03478-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [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: 08/30/2020] [Accepted: 11/02/2020] [Indexed: 11/30/2022] Open
Abstract
Background Reactive case detection (RACD) and foci investigation are key strategies in malaria elimination and prevention of its re-establishment. They are a key part of surveillance that has been recommended by the World Health Organization (WHO) to be considered as a core intervention and as one of the three pillars of the Global Technical Strategy for Malaria 2016–2030. Methods A search using the key words “Reactive Case Detection”, “RACD”, “RCD” and “Malaria” was carried out in PubMed, Scopus, Taylor and Francis online databases for studies published until 31st July 2019. The inclusion criteria for selection of articles for review included (1) how RACD is implemented in each country; (2) challenges faced in RACD implementation; (3) suggestions on how the effectiveness of RACD process can be improved. Results 411 titles were identified, 41 full text articles were screened and 29 were found eligible for inclusion in the review. Published literature on RACD, and case and foci investigations has mostly assessed the process of the activity. Most studies have documented that the yield of positives in RACD has been highest in the index case’s household and the immediate neighbourhood of the index case. Microscopy and RDTs are the common tests used in RACD. The guidelines for case and foci investigation, and RACD and PACD, are not universally adopted and are country-specific. Some of the limitations and challenges identified include lack of proper guidelines, logistic issues and problems with public compliance. Conclusions Although there is no documented evidence that RACD is useful in malaria elimination settings, most authors have opined that RACD is necessary for malaria elimination. Lack of knowledge in the target populations, a target radius and how to carry out the RACD process is a major challenge in the decision-making process.
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Affiliation(s)
- Ruwanthi Perera
- Department of Public Health, Faculty of Medicine, University of Kelaniya, P. O. Box 6, Thalagolla Road, Ragama, 11010, Sri Lanka
| | - Amandhi Caldera
- Department of Public Health, Faculty of Medicine, University of Kelaniya, P. O. Box 6, Thalagolla Road, Ragama, 11010, Sri Lanka
| | - A Rajitha Wickremasinghe
- Department of Public Health, Faculty of Medicine, University of Kelaniya, P. O. Box 6, Thalagolla Road, Ragama, 11010, Sri Lanka.
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10
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Bhondoekhan FRP, Searle KM, Hamapumbu H, Lubinda M, Matoba J, Musonda M, Katowa B, Shields TM, Kobayashi T, Norris DE, Curriero FC, Stevenson JC, Thuma PE, Moss WJ. Improving the efficiency of reactive case detection for malaria elimination in southern Zambia: a cross-sectional study. Malar J 2020; 19:175. [PMID: 32381005 PMCID: PMC7206707 DOI: 10.1186/s12936-020-03245-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [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: 01/20/2020] [Accepted: 04/23/2020] [Indexed: 01/20/2023] Open
Abstract
Background Reactive case detection (RCD) seeks to enhance malaria surveillance and control by identifying and treating parasitaemic individuals residing near index cases. In Zambia, this strategy starts with passive detection of symptomatic incident malaria cases at local health facilities or by community health workers, with subsequent home visits to screen-and-treat residents in the index case and neighbouring (secondary) households within a 140-m radius using rapid diagnostic tests (RDTs). However, a small circular radius may not be the most efficient strategy to identify parasitaemic individuals in low-endemic areas with hotspots of malaria transmission. To evaluate if RCD efficiency could be improved by increasing the probability of identifying parasitaemic residents, environmental risk factors and a larger screening radius (250 m) were assessed in a region of low malaria endemicity. Methods Between January 12, 2015 and July 26, 2017, 4170 individuals residing in 158 index and 531 secondary households were enrolled and completed a baseline questionnaire in the catchment area of Macha Hospital in Choma District, Southern Province, Zambia. Plasmodium falciparum prevalence was measured using PfHRP2 RDTs and quantitative PCR (qPCR). A Quickbird™ high-resolution satellite image of the catchment area was used to create environmental risk factors in ArcGIS, and generalized estimating equations were used to evaluate associations between risk factors and secondary households with parasitaemic individuals. Results The parasite prevalence in secondary (non-index case) households was 0.7% by RDT and 1.8% by qPCR. Overall, 8.5% (n = 45) of secondary households had at least one resident with parasitaemia by qPCR or RDT. The risk of a secondary household having a parasitaemic resident was significantly increased in proximity to higher order streams and marginally with increasing distance from index households. The adjusted OR for proximity to third- and fifth-order streams were 2.97 (95% CI 1.04–8.42) and 2.30 (95% CI 1.04–5.09), respectively, and that for distance to index households for each 50 m was 1.24 (95% CI 0.98–1.58). Conclusion Applying proximity to streams as a screening tool, 16% (n = 3) more malaria-positive secondary households were identified compared to using a 140-m circular screening radius. This analysis highlights the potential use of environmental risk factors as a screening strategy to increase RCD efficiency.
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Affiliation(s)
- Fiona R P Bhondoekhan
- MACS/WIHS Combined Cohort Study, Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
| | - Kelly M Searle
- MACS/WIHS Combined Cohort Study, Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.,Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, USA
| | | | | | | | | | - Ben Katowa
- Macha Research Trust, Choma District, Zambia
| | - Timothy M Shields
- MACS/WIHS Combined Cohort Study, Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Tamaki Kobayashi
- MACS/WIHS Combined Cohort Study, Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Douglas E Norris
- Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Frank C Curriero
- MACS/WIHS Combined Cohort Study, Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Jennifer C Stevenson
- Macha Research Trust, Choma District, Zambia.,Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Philip E Thuma
- Macha Research Trust, Choma District, Zambia.,Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - William J Moss
- MACS/WIHS Combined Cohort Study, Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.,Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
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11
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Chitnis N, Pemberton-Ross P, Yukich J, Hamainza B, Miller J, Reiker T, Eisele TP, Smith TA. Theory of reactive interventions in the elimination and control of malaria. Malar J 2019; 18:266. [PMID: 31375094 PMCID: PMC6679501 DOI: 10.1186/s12936-019-2882-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [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] [Received: 04/29/2019] [Accepted: 07/18/2019] [Indexed: 11/23/2022] Open
Abstract
Background Reactive case detection (RCD) is an integral part of many malaria control and elimination programmes and can be conceived of as a way of gradually decreasing transmission. However, it is unclear under what circumstances RCD may have a substantial impact on prevalence, how likely it is to lead to local elimination, or how effective it needs to be to prevent reintroduction after transmission has been interrupted. Methods Analyses and simulations of a discrete time compartmental susceptible-infectious-susceptible (SIS) model were used to understand the mechanisms of how RCD changes transmission dynamics and estimate the impact of RCD programmes in a range of settings with varying patterns of transmission potential and programme characteristics. Prevalence survey data from recent studies in Zambia were used to capture the effects of spatial clustering of patent infections. Results RCD proved most effective at low prevalence. Increasing the number of index cases followed was more important than increasing the number of neighbours tested per index case. Elimination was achieved only in simulations of situations with very low transmission intensity and following many index cases. However, RCD appears to be helpful in maintaining the disease-free state after achieving malaria elimination (through other interventions). Conclusion RCD alone can eliminate malaria in only a very limited range of settings, where transmission potential is very low, and improving the coverage of RCD has little effect on this range. In other settings, it is likely to reduce disease burden. RCD may also help maintain the disease-free state in the face of imported infections. Prevalence survey data can be used to estimate a targeting ratio (the ratio of prevalence found through RCD to that in the general population) which is an important determinant of the effect of RCD. Electronic supplementary material The online version of this article (10.1186/s12936-019-2882-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nakul Chitnis
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, 4051, Basel, Switzerland. .,University of Basel, Petersplatz 1, Basel, Switzerland.
| | - Peter Pemberton-Ross
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, 4051, Basel, Switzerland.,University of Basel, Petersplatz 1, Basel, Switzerland.,Amgen Europe GmbH: Rotkreuz, Zug, Switzerland
| | - Josh Yukich
- Center for Applied Malaria Research and Evaluation, Tulane University, School of Public Health and Tropical Medicine, New Orleans, LA, USA
| | - Busiku Hamainza
- National Malaria Control Centre, Ministry of Health, Lusaka, Zambia
| | - John Miller
- PATH Malaria Control and Evaluation Partnership in Africa (MACEPA), Lusaka, Zambia
| | - Theresa Reiker
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, 4051, Basel, Switzerland.,University of Basel, Petersplatz 1, Basel, Switzerland
| | - Thomas P Eisele
- Center for Applied Malaria Research and Evaluation, Tulane University, School of Public Health and Tropical Medicine, New Orleans, LA, USA
| | - Thomas A Smith
- Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, 4051, Basel, Switzerland.,University of Basel, Petersplatz 1, Basel, Switzerland
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12
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Karunasena VM, Marasinghe M, Koo C, Amarasinghe S, Senaratne AS, Hasantha R, Hewavitharana M, Hapuarachchi HC, Herath HDB, Wickremasinghe R, Mendis KN, Fernando D, Ranaweera D. The first introduced malaria case reported from Sri Lanka after elimination: implications for preventing the re-introduction of malaria in recently eliminated countries. Malar J 2019; 18:210. [PMID: 31234941 PMCID: PMC6591994 DOI: 10.1186/s12936-019-2843-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 06/17/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND There has been no local transmission of malaria in Sri Lanka for 6 years following elimination of the disease in 2012. Malaria vectors are prevalent in parts of the country, and imported malaria cases continue to be reported. The country is therefore at risk of malaria being re-established. The first case of introduced vivax malaria in the country is reported here, and the surveillance and response system that contained the further spread of this infection is described. METHODS Diagnosis of malaria was based on microscopy and rapid diagnostic tests. Entomological surveillance for anophelines used standard techniques for larval and adult surveys. Genotyping of parasite isolates was done using a multi-locus direct sequencing approach, combined with cloning and restriction fragment length polymorphism analyses. Treatment of vivax malaria infections was according to the national malaria treatment guidelines. RESULTS An imported vivax malaria case was detected in a foreign migrant followed by a Plasmodium vivax infection in a Sri Lankan national who visited the residence of the former. The link between the two cases was established by tracing the occurrence of events and by demonstrating genetic identity between the parasite isolates. Effective surveillance was conducted, and a prompt response was mounted by the Anti Malaria Campaign. No further transmission occurred as a result. CONCLUSIONS Evidence points to the case of malaria in the Sri Lankan national being an introduced malaria case transmitted locally from an infection in the foreign migrant labourer, which was the index case. Case detection, treatment and investigation, followed by prompt action prevented further transmission of these infections. Entomological surveillance and vector control at the site of transmission were critically important to prevent further transmission. The case is a reminder that the risk of re-establishment of the disease in the country is high, and that the surveillance and response system needs to be sustained in this form at least until the Southeast Asian region is free of malaria. Several countries that are on track to eliminate malaria in the coming years are in a similar situation of receptivity and vulnerability. Regional elimination of malaria must therefore be considered a priority if the gains of global malaria elimination are to be sustained.
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Affiliation(s)
| | - Manonath Marasinghe
- Anti Malaria Campaign Headquarters, 555/5 Public Health Building, Narehenpita, Colombo 5, Sri Lanka
| | - Carmen Koo
- Environmental Health Institute, National Environment Agency, Singapore, Singapore
| | | | - Arundika S Senaratne
- Anti Malaria Campaign Headquarters, 555/5 Public Health Building, Narehenpita, Colombo 5, Sri Lanka
| | | | - Mihirini Hewavitharana
- Anti Malaria Campaign Headquarters, 555/5 Public Health Building, Narehenpita, Colombo 5, Sri Lanka
| | | | - Hema D B Herath
- Anti Malaria Campaign Headquarters, 555/5 Public Health Building, Narehenpita, Colombo 5, Sri Lanka
| | - Rajitha Wickremasinghe
- Department of Public Health, Faculty of Medicine, University of Kelaniya, Kelaniya, Sri Lanka
| | | | - Deepika Fernando
- Department of Parasitology, Faculty of Medicine, Colombo, Sri Lanka.
| | - Dewanee Ranaweera
- Anti Malaria Campaign Headquarters, 555/5 Public Health Building, Narehenpita, Colombo 5, Sri Lanka
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13
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Zemene E, Koepfli C, Tiruneh A, Yeshiwondim AK, Seyoum D, Lee MC, Yan G, Yewhalaw D. Detection of foci of residual malaria transmission through reactive case detection in Ethiopia. Malar J 2018; 17:390. [PMID: 30367636 PMCID: PMC6203988 DOI: 10.1186/s12936-018-2537-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [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: 05/30/2018] [Accepted: 10/20/2018] [Indexed: 12/18/2022] Open
Abstract
Background Sub-microscopic and asymptomatic infections could be bottlenecks to malaria elimination efforts in Ethiopia. This study determined the prevalence of malaria, and individual and household-level factors associated with Plasmodium infections obtained following detection of index cases in health facilities in Jimma Zone. Methods Index malaria cases were passively detected and tracked in health facilities from June to November 2016. Moreover, family members of the index houses and neighbours located within approximately 200 m from the index houses were also screened for malaria. Results A total of 39 index cases initiated the reactive case detection of 726 individuals in 116 households. Overall, the prevalence of malaria using microscopy and PCR was 4.0% and 8.96%, respectively. Seventeen (43.6%) of the index cases were from Doyo Yaya kebele, where parasite prevalence was higher. The majority of the malaria cases (90.74%) were asymptomatic. Fever (AOR = 12.68, 95% CI 3.34–48.18) and history of malaria in the preceding 1 year (AOR = 3.62, 95% CI 1.77–7.38) were significant individual-level factors associated with detection of Plasmodium infection. Moreover, living in index house (AOR = 2.22, 95% CI 1.16–4.27), house with eave (AOR = 2.28, 95% CI 1.14–4.55), area of residence (AOR = 6.81, 95% CI 2.49–18.63) and family size (AOR = 3.35, 95% CI 1.53–7.33) were main household-level predictors for residual malaria transmission. Conclusion The number of index cases per kebele may enhance RACD efforts to detect additional malaria cases in low transmission settings. Asymptomatic and sub-microscopic infections were high in the study area, which need new or improved surveillance tools for malaria elimination efforts.
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Affiliation(s)
- Endalew Zemene
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia.
| | - Cristian Koepfli
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, 92697, USA
| | - Abebaw Tiruneh
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia
| | | | - Dinberu Seyoum
- Department of Statistics, College of Natural Sciences, Jimma University, Jimma, Ethiopia
| | - Ming-Chieh Lee
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, 92697, USA
| | - Guiyun Yan
- Program in Public Health, College of Health Sciences, University of California at Irvine, Irvine, CA, 92697, USA
| | - Delenasaw Yewhalaw
- School of Medical Laboratory Sciences, Faculty of Health Sciences, Jimma University, Jimma, Ethiopia.,Tropical and Infectious Diseases Research Centre, Jimma University, Jimma, Ethiopia
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14
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Kyaw AMM, Kathirvel S, Das M, Thapa B, Linn NYY, Maung TM, Lin Z, Thi A. "Alert-Audit-Act": assessment of surveillance and response strategy for malaria elimination in three low-endemic settings of Myanmar in 2016. Trop Med Health 2018; 46:11. [PMID: 29686526 PMCID: PMC5898078 DOI: 10.1186/s41182-018-0092-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [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: 01/16/2018] [Accepted: 03/21/2018] [Indexed: 11/21/2022] Open
Abstract
Background Myanmar, a malaria endemic country of Southeast Asia, adopted surveillance and response strategy similar to “1-3-7” Chinese strategy to achieve sub-national elimination in six low-endemic region/states of the country. Among these, Yangon, Bago-East, and Mon region/states have implemented this malaria surveillance and response strategy with modification in 2016. The current study was conducted to assess the case notification, investigation, classification, and response strategy (NICR) in these three states. Methods This was a retrospective cohort study using routine program data of all patients with malaria diagnosed and reported under the National Malaria Control Programme in 2016 from the above three states. As per the program, all malaria cases need to be notified within 1 day and investigated within 3 days of diagnosis and response to control (active case detection and control) should be taken for all indigenous malaria cases within 7 days of diagnosis. Results A total of 959 malaria cases were diagnosed from the study area in 2016. Of these, the case NICR details were available only for 312 (32.5%) malaria cases. Of 312 cases, the case notification, investigation, and classification were carried out within 3 days of malaria diagnosis in 95.5% cases (298/312). Of 208 indigenous malaria cases (66.7%, 208/312), response to control was taken in 96.6% (201/208) within 7 days of diagnosis. Conclusion The timeline at each stage of the strategy namely case notification, investigation, classification, and response to control was followed, and response action was taken in nearly all indigenous malaria cases for the available case information. Strengthening of health information and monitoring system is needed to avoid missing information. Future research on feasibility of mobile/tablet-based surveillance system and providing response to all cases including imported malaria can be further studied.
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Affiliation(s)
- Aye Mon Mon Kyaw
- National Malaria Control Programme/Vector Borne Disease Control, Department of Public Health, Ministry of Health and Sports, Nay Pyi Taw, Myanmar
| | - Soundappan Kathirvel
- International Union Against Tuberculosis and Lung Disease, Southeast Asia, New Delhi, India.,3Department of Community Medicine, School of Public Health, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Mrinalini Das
- Médecins Sans Frontières (MSF) OCB, New Delhi, India
| | - Badri Thapa
- World Health Organization Country Office for Myanmar, Yangon, Myanmar
| | - Nay Yi Yi Linn
- National Malaria Control Programme/Vector Borne Disease Control, Department of Public Health, Ministry of Health and Sports, Nay Pyi Taw, Myanmar
| | - Thae Maung Maung
- Department of Medical Research, Ministry of Health and Sports, Nay Pyi Taw, Myanmar
| | - Zaw Lin
- National Malaria Control Programme/Vector Borne Disease Control, Department of Public Health, Ministry of Health and Sports, Nay Pyi Taw, Myanmar
| | - Aung Thi
- National Malaria Control Programme/Vector Borne Disease Control, Department of Public Health, Ministry of Health and Sports, Nay Pyi Taw, Myanmar
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15
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Aidoo EK, Afrane YA, Machani MG, Chebore W, Lawson BW, Atieli H, Kariuki S, Lee MC, Koepfli C, Zhou G, Githeko AK, Yan G. Reactive case detection of Plasmodium falciparum in western Kenya highlands: effective in identifying additional cases, yet limited effect on transmission. Malar J 2018; 17:111. [PMID: 29534709 DOI: 10.1186/s12936-018-2260-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Background Identifying asymptomatic reservoirs of malaria parasites using index cases as entry points into the community is potentially a cost-effective way towards achieving malaria elimination. Methods Within 1 year, 1430 confirmed malaria cases were identified in Marani hospital, western Kenya. Fifty cases were followed up, and 108 index case household members and 612 neighbours within a 100 m radius were screened. As controls, samples were collected from 510 individuals matched with index cases and located at a distance of ≥ 500 m from them. Infections were diagnosed by microscopy and PCR while simultaneously collecting malaria vectors indoor using pyrethrum spray catches. Results In the index case and neighbour households, the prevalence of infection was approximately twice as high as in control households (by PCR: index cases households: 28.9%, neighbours: 25.3%, matched controls: 12.9%). In index case households, the indoor vector density (Anopheles gambiae and Anopheles funestus) was higher (0.46 female/house/night) than in neighbouring (0.31 f/h/n) and control houses (0.29 f/h/n). Conclusions Screening index case households and neighbours approximately doubles the chance to detect asymptomatic infections compared to randomly selected households. However, even if all cases were followed up, only a small proportion (˂ 10%) of the asymptomatic reservoir in the population would have been identified. Control programmes need to weigh the increased chance to find cases around index cases vs. the logistical challenges to target this subgroup within the population.
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Larsen DA, Winters A, Cheelo S, Hamainza B, Kamuliwo M, Miller JM, Bridges DJ. Shifting the burden or expanding access to care? Assessing malaria trends following scale-up of community health worker malaria case management and reactive case detection. Malar J 2017; 16:441. [PMID: 29096632 DOI: 10.1186/s12936-017-2088-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 10/27/2017] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Malaria is a significant burden to health systems and is responsible for a large proportion of outpatient cases at health facilities in endemic regions. The scale-up of community management of malaria and reactive case detection likely affect both malaria cases and outpatient attendance at health facilities. Using health management information data from 2012 to 2013 this article examines health trends before and after the training of volunteer community health workers to test and treat malaria cases in Southern Province, Zambia. RESULTS An estimated 50% increase in monthly reported malaria infections was found when community health workers were involved with malaria testing and treating in the community (incidence rate ratio 1.52, p < 0.001). Furthermore, an estimated 6% decrease in outpatient attendance at the health facility was found when community health workers were involved with malaria testing and treating in the community. CONCLUSIONS These results suggest a large public health benefit to both community case management of malaria and reactive case detection. First, the capacity of the malaria surveillance system to identify malaria infections was increased by nearly one-third. Second, the outpatient attendance at health facilities was modestly decreased. Expanding the capacity of the malaria surveillance programme through systems such as community case management and reactive case detection is an important step toward malaria elimination.
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17
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Tejedor-Garavito N, Dlamini N, Pindolia D, Soble A, Ruktanonchai NW, Alegana V, Le Menach A, Ntshalintshali N, Dlamini B, Smith DL, Tatem AJ, Kunene S. Travel patterns and demographic characteristics of malaria cases in Swaziland, 2010-2014. Malar J 2017; 16:359. [PMID: 28886710 PMCID: PMC5591561 DOI: 10.1186/s12936-017-2004-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [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: 05/24/2017] [Accepted: 08/30/2017] [Indexed: 11/17/2022] Open
Abstract
Background As Swaziland progresses towards national malaria elimination, the importation of parasites into receptive areas becomes increasingly important. Imported infections have the potential to instigate local transmission and sustain local parasite reservoirs. Methods Travel histories from Swaziland’s routine surveillance data from January 2010 to June 2014 were extracted and analysed. The travel patterns and demographics of rapid diagnostic test (RDT)-confirmed positive cases identified through passive and reactive case detection (RACD) were analysed and compared to those found to be negative through RACD. Results Of 1517 confirmed cases identified through passive surveillance, 67% reported travel history. A large proportion of positive cases reported domestic or international travel history (65%) compared to negative cases (10%). The primary risk factor for malaria infection in Swaziland was shown to be travel, more specifically international travel to Mozambique by 25- to 44-year old males, who spent on average 28 nights away. Maputo City, Inhambane and Gaza districts were the most likely travel destinations in Mozambique, and 96% of RDT-positive international travellers were either Swazi (52%) or Mozambican (44%) nationals, with Swazis being more likely to test negative. All international travellers were unlikely to have a bed net at home or use protection of any type while travelling. Additionally, paths of transmission, important border crossings and means of transport were identified. Conclusion Results from this analysis can be used to direct national and well as cross-border targeting of interventions, over space, time and by sub-population. The results also highlight that collaboration between neighbouring countries is needed to tackle the importation of malaria at the regional level. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-2004-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | - Adam Soble
- Clinton Health Access Initiative, Boston, MA, USA
| | - Nick W Ruktanonchai
- WorldPop, University of Southampton, Southampton, UK.,Flowminder Foundation, Stockholm, Sweden
| | - Victor Alegana
- WorldPop, University of Southampton, Southampton, UK.,Flowminder Foundation, Stockholm, Sweden
| | | | | | | | - David L Smith
- Institute for Health Metrics and Evaluation, University of Washington, Seattle, USA
| | - Andrew J Tatem
- WorldPop, University of Southampton, Southampton, UK.,Flowminder Foundation, Stockholm, Sweden
| | - Simon Kunene
- National Malaria Control Programme, Manzini, Swaziland
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18
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Yukich J, Bennett A, Yukich R, Stuck L, Hamainza B, Silumbe K, Smith T, Chitnis N, Steketee RW, Finn T, Eisele TP, Miller JM. Estimation of malaria parasite reservoir coverage using reactive case detection and active community fever screening from census data with rapid diagnostic tests in southern Zambia: a re-sampling approach. Malar J 2017; 16:317. [PMID: 28784122 PMCID: PMC5547485 DOI: 10.1186/s12936-017-1962-1] [Citation(s) in RCA: 14] [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] [Received: 03/06/2017] [Accepted: 07/29/2017] [Indexed: 12/21/2022] Open
Abstract
Background and methods In areas where malaria transmission has been suppressed by vector control interventions many malaria control and elimination programmes are actively seeking new interventions to further reduce malaria prevalence, incidence and transmission. Malaria infection prevalence and incidence has been shown to cluster geographically, especially at lower transmission levels, and as such a reactive strategy is frequently used, by which index cases presenting to a passive surveillance system are used to target small areas for testing and treatment, reactive case detection (RCD), or focal drug administration (fDA). This study utilizes geo-located data from a census with parasitological testing with rapid diagnostic tests (RDTs) and treatment-seeking data collection conducted in southern Zambia to estimate the coverage of RCD or fDA in terms of the population and parasite reservoir as well as the operational requirements of such strategies, using a re-sampling algorithm developed exclusively for this purpose. This re-sampling algorithm allows for the specification of several parameters, such that different operational variants of these reactive strategies can be examined, including varying the search radius, screening for fever, or presumptive treatment (fDA). Results Results indicate that RCD, fDA and active fever screening followed by RCD, even with search radii over several hundered meters will only yield limited coverage of the RDT positive parasite reservoir during a short period. Long-term use of these strategies may increase this proportion. Reactive strategies detect a higher proportion of the reservoir of infections than random searches, but this effect appears to be greater in areas of low, but not moderate malaria prevalence in southern Zambia. Discussion Increases in the sensitivity of RDTs could also affect these results. The number of individuals and households that need to be searched increase rapidly, but approximately linearly with search radius. Conclusions Reactive strategies in southern Zambia yield improved identification of the parasite reservoir when targeted to areas with prevalence less than 10%. The operational requirements of delivering reactive strategies routinely are likely to prevent their uptake until prevalence falls far below this level.
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Affiliation(s)
- Joshua Yukich
- Center for Applied Malaria Research and Evaluation (CAMRE), Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, 70112, United States.
| | - Adam Bennett
- Global Health Group, University of California San Francisco, San Francisco, CA, United States
| | - Rudy Yukich
- Sensorstar Inc., Ellicott City, MD, United States
| | - Logan Stuck
- Center for Applied Malaria Research and Evaluation (CAMRE), Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, 70112, United States
| | - Busiku Hamainza
- National Malaria Control Centre, Ministry of Health, Lusaka, Zambia
| | - Kafula Silumbe
- Malaria Control and Elimination Partnership in Africa (MACEPA), PATH, Lusaka, Zambia
| | - Tom Smith
- Swiss Tropical and Public Health Institute, and University of Basel, Basel, CH, Switzerland
| | - Nakul Chitnis
- Swiss Tropical and Public Health Institute, and University of Basel, Basel, CH, Switzerland
| | - Richard W Steketee
- Malaria Control and Elimination Partnership in Africa (MACEPA), PATH, Lusaka, Zambia
| | - Timothy Finn
- Center for Applied Malaria Research and Evaluation (CAMRE), Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, 70112, United States
| | - Thomas P Eisele
- Center for Applied Malaria Research and Evaluation (CAMRE), Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, 70112, United States
| | - John M Miller
- Malaria Control and Elimination Partnership in Africa (MACEPA), PATH, Lusaka, Zambia
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19
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Gerardin J, Bever CA, Bridenbecker D, Hamainza B, Silumbe K, Miller JM, Eisele TP, Eckhoff PA, Wenger EA. Effectiveness of reactive case detection for malaria elimination in three archetypical transmission settings: a modelling study. Malar J 2017; 16:248. [PMID: 28606143 PMCID: PMC5469005 DOI: 10.1186/s12936-017-1903-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [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: 03/01/2017] [Accepted: 06/07/2017] [Indexed: 11/21/2022] Open
Abstract
Background Reactive case detection could be a powerful tool in malaria elimination, as it selectively targets transmission pockets. However, field operations have yet to demonstrate under which conditions, if any, reactive case detection is best poised to push a region to elimination. This study uses mathematical modelling to assess how baseline transmission intensity and local interconnectedness affect the impact of reactive activities in the context of other possible intervention packages. Methods Communities in Southern Province, Zambia, where elimination operations are currently underway, were used as representatives of three archetypes of malaria transmission: low-transmission, high household density; high-transmission, low household density; and high-transmission, high household density. Transmission at the spatially-connected household level was simulated with a dynamical model of malaria transmission, and local variation in vectorial capacity and intervention coverage were parameterized according to data collected from the area. Various potential intervention packages were imposed on each of the archetypical settings and the resulting likelihoods of elimination by the end of 2020 were compared. Results Simulations predict that success of elimination campaigns in both low- and high-transmission areas is strongly dependent on stemming the flow of imported infections, underscoring the need for regional-scale strategies capable of reducing transmission concurrently across many connected areas. In historically low-transmission areas, treatment of clinical malaria should form the cornerstone of elimination operations, as most malaria infections in these areas are symptomatic and onward transmission would be mitigated through health system strengthening; reactive case detection has minimal impact in these settings. In historically high-transmission areas, vector control and case management are crucial for limiting outbreak size, and the asymptomatic reservoir must be addressed through reactive case detection or mass drug campaigns. Conclusions Reactive case detection is recommended only for settings where transmission has recently been reduced rather than all low-transmission settings. This is demonstrated in a modelling framework with strong out-of-sample accuracy across a range of transmission settings while including methodologies for understanding the most resource-effective allocations of health workers. This approach generalizes to providing a platform for planning rational scale-up of health systems based on locally-optimized impact according to simplified stratification. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1903-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | - Busiku Hamainza
- National Malaria Elimination Centre, Ministry of Health, Lusaka, Zambia
| | - Kafula Silumbe
- PATH Malaria Control and Elimination Partnership in Africa, Lusaka, Zambia
| | - John M Miller
- PATH Malaria Control and Elimination Partnership in Africa, Lusaka, Zambia
| | - Thomas P Eisele
- Center for Applied Malaria Research and Evaluation, Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA
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20
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Wang D, Cotter C, Sun X, Bennett A, Gosling RD, Xiao N. Adapting the local response for malaria elimination through evaluation of the 1-3-7 system performance in the China-Myanmar border region. Malar J 2017; 16:54. [PMID: 28137293 PMCID: PMC5282924 DOI: 10.1186/s12936-017-1707-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [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: 11/23/2016] [Accepted: 01/20/2017] [Indexed: 11/10/2022] Open
Abstract
Background Assessing the essential components of ‘1-3-7’ strategy along the China–Myanmar border is critical to identify gaps and challenges to support evidence-based decision making. Methods A mixed-method retrospective study including quantitative and qualitative analysis of the 1-3-7 system components was conducted. Sampled counties were chosen based on malaria incidence from 1 January 2012 to 31 December 2014. Results All 260 confirmed malaria cases from sampled counties were reported within 1 day and had completed case investigations. 70.0% of all Reactive Case Detection (RACD) events were conducted and 90.1% of those were within 7 days. Only ten additional individuals were found malaria positive out of 3662 individuals tested (0.3%) by rapid diagnostic test during RACD events. Conclusions Key gaps were identified in case investigation and RACD activities in Yunnan Province border counties. This evidence supports improving the RACD (or “7”) response strategy in this setting. Given the challenges in this border region, it will be critical to adapt the RACD response to promote the malaria elimination along the China border. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1707-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Duoquan Wang
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Pathology, World Health Organization Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, People's Republic of China
| | - Chris Cotter
- Malaria Elimination Initiative, Global Health Group, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Xiaodong Sun
- Yunnan Institute of Parasitic Diseases, Puer, 665000, People's Republic of China
| | - Adam Bennett
- Malaria Elimination Initiative, Global Health Group, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Roly D Gosling
- Malaria Elimination Initiative, Global Health Group, University of California, San Francisco, San Francisco, CA, 94158, USA
| | - Ning Xiao
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Key Laboratory of Parasite and Vector Pathology, World Health Organization Collaborating Centre for Tropical Diseases, National Center for International Research on Tropical Diseases, Shanghai, 200025, People's Republic of China.
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21
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Larsen DA, Ngwenya-Kangombe T, Cheelo S, Hamainza B, Miller J, Winters A, Bridges DJ. Location, location, location: environmental factors better predict malaria-positive individuals during reactive case detection than index case demographics in Southern Province, Zambia. Malar J 2017; 16:18. [PMID: 28061853 PMCID: PMC5219724 DOI: 10.1186/s12936-016-1649-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [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: 10/06/2016] [Accepted: 12/15/2016] [Indexed: 11/23/2022] Open
Abstract
Background Decreasing malaria transmission leads to increasing heterogeneity with increased risk in both hot spots (locations) and hot pops (certain demographics). In Southern Province, Zambia, reactive case detection has formed a part of malaria surveillance and elimination efforts since 2011. Various factors may be associated with finding malaria infections during case investigations, including the demographics of the incident case and environmental characteristics of the location of the incident case. Methods Community health worker registries were used to determine what factors were associated with finding a malaria infection during reactive case detection. Results Location was a more powerful predictor of finding malaria infections during case investigations than the demographics of the incident case. After accounting for environmental characteristics, no demographics around the incident case were associated with finding malaria infections during case investigations. Various time-invariant measures of the environment, such as median enhanced vegetation index, the topographic position index, the convergence index, and the topographical wetness index, were all associated as expected with increased probability of finding a malaria infection during case investigations. Conclusions These results suggest that targeting the locations highly at risk of malaria transmission is of importance in elimination settings.
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Affiliation(s)
- David A Larsen
- Department of Public Health, Food Studies and Nutrition, Syracuse University, 344D White Hall, Syracuse, NY, 13244, USA. .,Akros, Lusaka, Zambia.
| | | | | | | | | | - Anna Winters
- Akros, Lusaka, Zambia.,University of Montana School of Public and Community Health Science, Missoula, MT, USA
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22
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Parker DM, Landier J, von Seidlein L, Dondorp A, White L, Hanboonkunupakarn B, Maude RJ, Nosten FH. Limitations of malaria reactive case detection in an area of low and unstable transmission on the Myanmar-Thailand border. Malar J 2016; 15:571. [PMID: 27887652 PMCID: PMC5124267 DOI: 10.1186/s12936-016-1631-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [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: 09/05/2016] [Accepted: 11/21/2016] [Indexed: 11/10/2022] Open
Abstract
Background Reactive case detection is an approach that has been proposed as a tool for malaria elimination in low-transmission settings. It is an intuitively justified approach based on the concept of space–time clustering of malaria cases. When an index malaria clinical case is detected, it triggers reactive screening and treatment in the index house and neighbouring houses. However, the efficacy of this approach at varying screening radii and malaria prevalence remains ill defined. Methods Data were obtained from a detailed demographic and geographic surveillance study in four villages on the Myanmar–Thailand border. Clinical cases were recorded at village malaria clinics and were linked back to patients’ residencies. These data were used to simulate the efficacy of reactive case detection for clinical cases using rapid diagnostic tests (RDT). Simulations took clinical cases in a given month and tabulated the number of cases that would have been detected in the following month at varying screening radii around the index houses. Simulations were run independently for both falciparum and vivax malaria. Each simulation of a reactive case detection effort was run in comparison with a strategy using random selection of houses for screening. Results In approximately half of the screenings for falciparum and 10% for vivax it would have been impossible to detect any malaria cases regardless of the screening strategy because the screening would have occurred during times when there were no cases. When geographically linked cases were present in the simulation, reactive case detection would have only been successful at detecting most malaria cases using larger screening radii (150-m radius and above). At this screening radius and above, reactive case detection does not perform better than random screening of an equal number of houses in the village. Screening within very small radii detects only a very small proportion of cases, but despite this low performance is better than random screening with the same sample size. Conclusions The results of these simulations indicate that reactive case detection for clinical cases using RDTs has limited ability in halting transmission in regions of low and unstable transmission. This is linked to high spatial heterogeneity of cases, acquisition of malaria infections outside the village, as well missing asymptomatic infections. When cases are few and sporadic, reactive case detection would result in major time and budgetary losses. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1631-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniel M Parker
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Tak, Thailand.
| | - Jordi Landier
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Tak, Thailand
| | - Lorenz von Seidlein
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Arjen Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | - Lisa White
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
| | | | - Richard J Maude
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Tak, Thailand.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK.,Harvard T.H. Chan School of Public Health, Harvard University, Boston, USA
| | - François H Nosten
- Shoklo Malaria Research Unit, Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Mae Sot, Tak, Thailand.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
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23
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Herdiana H, Cotter C, Coutrier FN, Zarlinda I, Zelman BW, Tirta YK, Greenhouse B, Gosling RD, Baker P, Whittaker M, Hsiang MS. Malaria risk factor assessment using active and passive surveillance data from Aceh Besar, Indonesia, a low endemic, malaria elimination setting with Plasmodium knowlesi, Plasmodium vivax, and Plasmodium falciparum. Malar J 2016; 15:468. [PMID: 27619000 PMCID: PMC5020529 DOI: 10.1186/s12936-016-1523-z] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [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: 07/01/2016] [Accepted: 09/06/2016] [Indexed: 12/03/2022] Open
Abstract
Background As malaria transmission declines, it becomes more geographically focused and more likely due to asymptomatic and non-falciparum infections. To inform malaria elimination planning in the context of this changing epidemiology, local assessments on the risk factors for malaria infection are necessary, yet challenging due to the low number of malaria cases. Methods A population-based, cross-sectional study was performed using passive and active surveillance data collected in Aceh Besar District, Indonesia from 2014 to 2015. Malaria infection was defined as symptomatic polymerase chain reaction (PCR)-confirmed infection in index cases reported from health facilities, and asymptomatic or symptomatic PCR-confirmed infection identified in reactive case detection (RACD). Potential risk factors for any infection, species-specific infection, or secondary-case detection in RACD were assessed through questionnaires and evaluated for associations. Results Nineteen Plasmodium knowlesi, 12 Plasmodium vivax and six Plasmodium falciparum cases were identified passively, and 1495 community members screened in RACD, of which six secondary cases were detected (one P. knowlesi, three P. vivax, and two P. falciparum, with four being asymptomatic). Compared to non-infected subjects screened in RACD, cases identified through passive or active surveillance were more likely to be male (AOR 12.5, 95 % CI 3.0–52.1), adult (AOR 14.0, 95 % CI 2.2–89.6 for age 16–45 years compared to <15 years), have visited the forest in the previous month for any reason (AOR 5.6, 95 % CI 1.3–24.2), and have a workplace near or in the forest and requiring overnight stays (AOR 7.9, 95 % CI 1.6–39.7 compared to workplace not near or in the forest). Comparing subjects with infections of different species, differences were observed in sub-district of residence and other demographic and behavioural factors. Among subjects screened in RACD, cases compared to non-cases were more likely to be febrile and reside within 100 m of the index case. Conclusion In this setting, risk of malaria infection in index and RACD identified cases was associated with forest exposure, particularly overnights in the forest for work. In low-transmission settings, utilization of data available through routine passive and active surveillance can support efforts to target individuals at high risk.
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Affiliation(s)
- Herdiana Herdiana
- School of Public Health, University of Queensland, Brisbane, QLD, Australia.,United Nations Children's Fund (UNICEF), Aceh Field Office, Banda Aceh, Indonesia
| | - Chris Cotter
- Malaria Elimination Initiative, Global Health Group, University of California San Francisco (UCSF), San Francisco, CA, USA
| | | | - Iska Zarlinda
- Eijkman Institute for Molecular Biology, Jakarta, Indonesia
| | - Brittany W Zelman
- Malaria Elimination Initiative, Global Health Group, University of California San Francisco (UCSF), San Francisco, CA, USA
| | | | | | - Roly D Gosling
- Malaria Elimination Initiative, Global Health Group, University of California San Francisco (UCSF), San Francisco, CA, USA
| | - Peter Baker
- School of Public Health, University of Queensland, Brisbane, QLD, Australia
| | - Maxine Whittaker
- School of Public Health, University of Queensland, Brisbane, QLD, Australia.,College of Public Health, Medical and Veterinary Sciences, University of James Cook, Townsville, QLD, Australia
| | - Michelle S Hsiang
- Malaria Elimination Initiative, Global Health Group, University of California San Francisco (UCSF), San Francisco, CA, USA. .,Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA. .,Department of Pediatrics, UCSF, San Francisco, CA, USA.
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24
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Searle KM, Hamapumbu H, Lubinda J, Shields TM, Pinchoff J, Kobayashi T, Stevenson JC, Bridges DJ, Larsen DA, Thuma PE, Moss WJ. Evaluation of the operational challenges in implementing reactive screen-and-treat and implications of reactive case detection strategies for malaria elimination in a region of low transmission in southern Zambia. Malar J 2016; 15:412. [PMID: 27527347 PMCID: PMC4986207 DOI: 10.1186/s12936-016-1460-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [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: 04/27/2016] [Accepted: 07/29/2016] [Indexed: 11/16/2022] Open
Abstract
Background As malaria transmission declines in many regions of sub-Saharan Africa, interventions to identify the asymptomatic reservoir are being deployed with the goals of improving surveillance and interrupting transmission. Reactive case detection strategies, in which individuals with clinical malaria are followed up at their home and household residents and neighbours are screened and treated for malaria, are increasingly used as part of malaria elimination programmes. Methods A reactive screen-and-treat programme was implemented by the National Malaria Control Centre in Southern Province, Zambia, in which individuals residing within 140 m of an index case were screened with a malaria rapid diagnostic test (RDT) and treated if positive. The operational challenges during the early stages of implementing this reactive screen-and-treat programme in the catchment area of Macha Hospital in Southern Province, Zambia were assessed using rural health centre records, ground truth evaluation of community health worker performance, and data from serial cross-sectional surveys. The proportion of individuals infected with Plasmodium falciparum who were identified and treated was estimated by simulating reactive screen-and-treat and focal drug administration cascades. Results Within the 1st year of implementation, community health workers followed up 32 % of eligible index cases. When index cases were followed up, 66 % of residents were at home in the index households and 58 % in neighbouring households. Forty-one neighbouring households of 26 index households were screened, but only 13 (32 %) were within the 140-m screening radius. The parasite prevalence by RDT was 22 % in index households and 5 % in neighbouring households. In a simulation model with complete follow-up, 22 % of the total infected population would be detected with reactive screen-and-treat but 57 % with reactive focal drug administration. Conclusions With limited resources, coverage and diagnostic tools, reactive screen-and-treat will likely not be sufficient to achieve malaria elimination in this setting. However, high coverage with reactive focal drug administration could be efficient at decreasing the reservoir of infection and should be considered as an alternative strategy. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1460-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kelly M Searle
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA. .,Johns Hopkins Malaria Research Institute, Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.
| | | | | | - Timothy M Shields
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.,Johns Hopkins Malaria Research Institute, Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Jessie Pinchoff
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.,Johns Hopkins Malaria Research Institute, Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Tamaki Kobayashi
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.,Johns Hopkins Malaria Research Institute, Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Jennifer C Stevenson
- Johns Hopkins Malaria Research Institute, Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.,Macha Research Trust, Choma District, Zambia
| | | | - David A Larsen
- Akros, Cresta Golfview Grounds, Great East Road, Lusaka, Zambia.,Department of Public Health, Food Studies and Nutrition, Syracuse University, Syracuse, NY, USA
| | - Philip E Thuma
- Johns Hopkins Malaria Research Institute, Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.,Macha Research Trust, Choma District, Zambia
| | - William J Moss
- Department of Epidemiology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA.,Johns Hopkins Malaria Research Institute, Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
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25
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Larson BA, Ngoma T, Silumbe K, Rutagwera MRI, Hamainza B, Winters AM, Miller JM, Scott CA. A framework for evaluating the costs of malaria elimination interventions: an application to reactive case detection in Southern Province of Zambia, 2014. Malar J 2016; 15:408. [PMID: 27515533 PMCID: PMC4982323 DOI: 10.1186/s12936-016-1457-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [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: 06/21/2016] [Accepted: 07/29/2016] [Indexed: 11/20/2022] Open
Abstract
Background This paper summarizes a framework for evaluating the costs of malaria elimination interventions and applies this approach to one key component of the elimination strategy—reactive case detection (RCD)—implemented through 173 health facilities across 10 districts in Southern Province of Zambia during 2014. Methods The primary unit of analysis is the health facility catchment area (HFCA). A five-step approach was followed to estimate implementation costs: organize preliminary information; estimate basic unit costs; estimate activity unit costs; estimate and organize final unit cost database; and create the final costing database (one row of data per HFCA). By working through a specific application, the overall logic of the analysis and details of each step are presented. An electronic annex also provides all details of the analysis. Because population varies substantially across HFCAs, all results are reported per 1000 population in HFCAs. Results During 2014, 38.9 households per HFCA were visited for RCD services; 166.8 individuals were tested and 32.3 tested positive and were treated. The mean annual cost per HFCA was $1177 (median = $923, IQR $651–$1417). Variation in costs was driven by the number of CHWs and passive cases detected. CHW-related costs and data review meetings accounted for the largest share of costs. Rapid diagnostic tests and drugs accounted for less than 10 % of total costs. Conclusions The framework presented here follows standard methods in applied costing of public health interventions (combining ingredients- and activity-based costing approaches into one final cost analysis). Through an application to a specific programme implemented in Zambia in 2014, the details of how to apply such methods to an actual programme are presented. Such details are not typically presented in existing costing analyses but are required for applied analysts working with national malaria control programmes and other organizations to complete such analyses as part of routine programme implementation. Obtaining data and information for implementing the approach remains complicated, in part because analysts from one organization may not have easy access to information from another organization. This basic approach is transparent and easily applied to other malaria elimination interventions being implemented in sub-Saharan Africa and elsewhere. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1457-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Bruce A Larson
- Department of Global Health, Boston University School of Public Health, 801 Massachusetts Avenue, Boston, MA, 80211, USA.
| | - Thandiwe Ngoma
- PATH Malaria Control and Elimination Partnership in Africa (MACEPA), National Malaria Control Centre, Chainama Hospital College Grounds, Great East Road, Lusaka, Zambia
| | - Kafula Silumbe
- PATH Malaria Control and Elimination Partnership in Africa (MACEPA), National Malaria Control Centre, Chainama Hospital College Grounds, Great East Road, Lusaka, Zambia
| | - Marie-Reine I Rutagwera
- PATH Malaria Control and Elimination Partnership in Africa (MACEPA), National Malaria Control Centre, Chainama Hospital College Grounds, Great East Road, Lusaka, Zambia
| | - Busiku Hamainza
- Ministry of Health, National Malaria Control Centre, Chainama Hospital College Grounds, Great East Road, P.O. Box 32509, Lusaka, Zambia
| | - Anna M Winters
- Akros, Cresta Golfview Grounds, Great East Road, Unit 5, Lusaka, Zambia.,University of Montana School of Public and Community Health Sciences, Missoula, MT, USA
| | - John M Miller
- PATH Malaria Control and Elimination Partnership in Africa (MACEPA), National Malaria Control Centre, Chainama Hospital College Grounds, Great East Road, Lusaka, Zambia
| | - Callie A Scott
- PATH Malaria Control and Elimination Partnership in Africa (MACEPA), 2201 Westlake Avenue, Suite 200, Seattle, WA, 98121, USA
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Lohfeld L, Kangombe-Ngwenya T, Winters AM, Chisha Z, Hamainza B, Kamuliwo M, Miller JM, Burns M, Bridges DJ. A qualitative review of implementer perceptions of the national community-level malaria surveillance system in Southern Province, Zambia. Malar J 2016; 15:400. [PMID: 27502213 PMCID: PMC4977701 DOI: 10.1186/s12936-016-1455-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [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: 01/06/2016] [Accepted: 07/28/2016] [Indexed: 11/12/2022] Open
Abstract
Background Parts of Zambia with very low malaria parasite prevalence and high coverage of vector control interventions are targeted for malaria elimination through a series of interventions including reactive case detection (RCD) at community level. When a symptomatic individual presenting to a community health worker (CHW) or government clinic is diagnostically confirmed as an incident malaria case an RCD response is initiated. This consists of a CHW screening the community around the incident case with rapid diagnostic tests (RDT) and treating positive cases with artemether-lumefantrine (AL, Coartem™) in accordance with national policy. Since its inception in 2011, Zambia’s RCD programme has relied on anecdotal feedback from staff to identify issues and possible solutions. In 2014, a systematic qualitative programme review was conducted to determine perceptions around malaria rates, incentives, operational challenges and solutions according to CHWs, their supervisors and district-level managers. Methods A criterion-based sampling framework based on training regime and performance level was used to select nine rural health posts in four districts of Southern Province. Twenty-two staff interviews were completed to produce English or bilingual (CiTonga or Silozi + English) verbatim transcripts, which were then analysed using thematic framework analysis. Results CHWs, their supervisors and district-level managers strongly credited the system with improving access to malaria services and significantly reducing the number of cases in their area. The main implementation barriers included access (e.g., lack of rain gear, broken bicycles), insufficient number of CHWs for programme coverage, communication (e.g. difficulties maintaining cell phones and “talk time” to transmit data by phone), and inconsistent supply chain (e.g., inadequate numbers of RDT kits and anti-malarial drugs to test and treat uncomplicated cases). Conclusions This review highlights the importance of a community surveillance system like RCD in shaping Zambia’s malaria elimination campaign by identifying community-based infections that might otherwise remain undetected. At this stage the system must ensure it can meet growing public demand by providing CHWs the tools and materials they need to consistently carry out their work and expand programme reach to more isolated communities. Results from this review will be used to plan programme scale-up into other parts of Zambia.
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Affiliation(s)
- Lynne Lohfeld
- Bachelor of Health Sciences (Honours) Program, McMaster University, Hamilton, ON, Canada
| | | | - Anna M Winters
- Akros, Cresta Golfview Grounds, Great East Road, Lusaka, Zambia
| | - Zunda Chisha
- Akros, Cresta Golfview Grounds, Great East Road, Lusaka, Zambia
| | - Busiku Hamainza
- National Malaria Control Centre, Government of Zambia Ministry of Health, Lusaka, Zambia
| | - Mulakwa Kamuliwo
- National Malaria Control Centre, Government of Zambia Ministry of Health, Lusaka, Zambia
| | - John M Miller
- Malaria Control and Evaluation Partnership in Africa (MACEPA/PATH), Lusaka, Zambia
| | - Matthew Burns
- Akros, Cresta Golfview Grounds, Great East Road, Lusaka, Zambia
| | - Daniel J Bridges
- Akros, Cresta Golfview Grounds, Great East Road, Lusaka, Zambia.
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