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OKeeffe J, Salem-Bango L, Desjardins MR, Lantagne D, Altare C, Kaur G, Heath T, Rangaiya K, Obroh POO, Audu A, Lecuyot B, Zoungrana T, Ihemezue EE, Aye S, Sikder M, Doocy S, Wang Q, Xiao M, Spiegel PB. Case-area targeted interventions during a large-scale cholera epidemic: A prospective cohort study in Northeast Nigeria. PLoS Med 2024; 21:e1004404. [PMID: 38728366 PMCID: PMC11149837 DOI: 10.1371/journal.pmed.1004404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 06/04/2024] [Accepted: 04/17/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND Cholera outbreaks are on the rise globally, with conflict-affected settings particularly at risk. Case-area targeted interventions (CATIs), a strategy whereby teams provide a package of interventions to case and neighboring households within a predefined "ring," are increasingly employed in cholera responses. However, evidence on their ability to attenuate incidence is limited. METHODS AND FINDINGS We conducted a prospective observational cohort study in 3 conflict-affected states in Nigeria in 2021. Enumerators within rapid response teams observed CATI implementation during a cholera outbreak and collected data on household demographics; existing water, sanitation, and hygiene (WASH) infrastructure; and CATI interventions. Descriptive statistics showed that CATIs were delivered to 46,864 case and neighbor households, with 80.0% of cases and 33.5% of neighbors receiving all intended supplies and activities, in a context with operational challenges of population density, supply stock outs, and security constraints. We then applied prospective Poisson space-time scan statistics (STSS) across 3 models for each state: (1) an unadjusted model with case and population data; (2) an environmentally adjusted model adjusting for distance to cholera treatment centers and existing WASH infrastructure (improved water source, improved latrine, and handwashing station); and (3) a fully adjusted model adjusting for environmental and CATI variables (supply of Aquatabs and soap, hygiene promotion, bedding and latrine disinfection activities, ring coverage, and response timeliness). We ran the STSS each day of our study period to evaluate the space-time dynamics of the cholera outbreaks. Compared to the unadjusted model, significant cholera clustering was attenuated in the environmentally adjusted model (from 572 to 18 clusters) but there was still risk of cholera transmission. Two states still yielded significant clusters (range 8-10 total clusters, relative risk of 2.2-5.5, 16.6-19.9 day duration, including 11.1-56.8 cholera cases). Cholera clustering was completely attenuated in the fully adjusted model, with no significant anomalous clusters across time and space. Associated measures including quantity, relative risk, significance, likelihood of recurrence, size, and duration of clusters reinforced the results. Key limitations include selection bias, remote data monitoring, and the lack of a control group. CONCLUSIONS CATIs were associated with significant reductions in cholera clustering in Northeast Nigeria despite operational challenges. Our results provide a strong justification for rapid implementation and scale-up CATIs in cholera-response, particularly in conflict settings where WASH access is often limited.
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Affiliation(s)
- Jennifer OKeeffe
- Center for Humanitarian Health, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Lindsay Salem-Bango
- Center for Humanitarian Health, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Michael R. Desjardins
- Spatial Science for Public Health Center, Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Daniele Lantagne
- Lancon Environmental, LLC, Somerville, Massachusetts, United States of America
| | - Chiara Altare
- Center for Humanitarian Health, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Gurpreet Kaur
- Center for Humanitarian Health, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | | | | | | | | | | | | | | | - Solomon Aye
- Solidarités International, Maiduguri, Nigeria
| | - Mustafa Sikder
- Center for Humanitarian Health, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Shannon Doocy
- Center for Humanitarian Health, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Qiulin Wang
- Center for Humanitarian Health, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Melody Xiao
- Center for Humanitarian Health, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Paul B. Spiegel
- Center for Humanitarian Health, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
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Taty N, Bompangue D, de Richemond NM, Muyembe JJ. Spatiotemporal dynamics of cholera in the Democratic Republic of the Congo before and during the implementation of the Multisectoral Cholera Elimination Plan: a cross-sectional study from 2000 to 2021. BMC Public Health 2023; 23:1592. [PMID: 37608355 PMCID: PMC10463990 DOI: 10.1186/s12889-023-16449-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 08/03/2023] [Indexed: 08/24/2023] Open
Abstract
BACKGROUND The Democratic Republic of the Congo (DRC) implemented the first strategic Multisectoral Cholera Elimination Plan (MCEP) in 2008-2012. Two subsequent MCEPs have since been implemented covering the periods 2013-2017 and 2018-2021. The current study aimed to assess the spatiotemporal dynamics of cholera over the recent 22-year period to determine the impact of the MCEPs on cholera epidemics, establish lessons learned and provide an evidence-based foundation to improve the implementation of the next MCEP (2023-2027). METHODS In this cross-sectional study, secondary weekly epidemiological cholera data covering the 2000-2021 period was extracted from the DRC Ministry of Health surveillance databases. The data series was divided into four periods: pre-MCEP 2003-2007 (pre-MCEP), first MCEP (MCEP-1), second MCEP (MCEP-2) and third MCEP (MCEP-3). For each period, we assessed the overall cholera profiles and seasonal patterns. We analyzed the spatial dynamics and identified cholera risk clusters at the province level. We also assessed the evolution of cholera sanctuary zones identified during each period. RESULTS During the 2000-2021 period, the DRC recorded 520,024 suspected cases and 12,561 deaths. The endemic provinces remain the most affected with more than 75% of cases, five of the six endemic provinces were identified as risk clusters during each MCEP period (North Kivu, South Kivu, Tanganyika, Haut-Lomami and Haut-Katanga). Several health zones were identified as cholera sanctuary zones during the study period: 14 health zones during MCEP-1, 14 health zones during MCEP-2 and 29 health zones during MCEP-3. Over the course of the study period, seasonal cholera patterns remained constant, with one peak during the dry season and one peak during the rainy season. CONCLUSION Despite the implementation of three MCEPs, the cholera context in the DRC remains largely unchanged since the pre-MCEP period. To better orient cholera elimination activities, the method used to classify priority health zones should be optimized by analyzing epidemiological; water, sanitation and hygiene; socio-economic; environmental and health indicators at the local level. Improvements should also be made regarding the implementation of the MCEP, reporting of funded activities and surveillance of cholera cases. Additional studies should aim to identify specific bottlenecks and gaps in the coordination and strategic efforts of cholera elimination interventions at the local, national and international levels.
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Affiliation(s)
- Nadège Taty
- Laboratoire de géographie et d'aménagement de Montpellier, Université Paul Valéry Montpellier 3, Montpellier, France.
- Service d'Ecologie et Contrôle des Maladies Infectieuses, Faculté de Médecine, Université de Kinshasa, République démocratique, Congo.
- Programme National d'Elimination du choléra et de lutte contre les autres maladies diarrhéiques, Ministère de la Santé, Hygiène et Prévention, République démocratique, Congo.
| | - Didier Bompangue
- Service d'Ecologie et Contrôle des Maladies Infectieuses, Faculté de Médecine, Université de Kinshasa, République démocratique, Congo
- Programme National d'Elimination du choléra et de lutte contre les autres maladies diarrhéiques, Ministère de la Santé, Hygiène et Prévention, République démocratique, Congo
- Laboratory Chrono-Environnement, UMR 6249, University of Bourgogne Franche-Comté, Besançon, France
| | - Nancy Meschinet de Richemond
- Laboratoire de géographie et d'aménagement de Montpellier, Université Paul Valéry Montpellier 3, Montpellier, France
| | - J J Muyembe
- Institut National des Recherches Biomédicales, Kinshasa, Democratic Republic of the Congo
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Kayembe HC, Bompangue D, Linard C, Mandja BA, Batumbo D, Matunga M, Muwonga J, Moutschen M, Situakibanza H, Ozer P. Drivers of the dynamics of the spread of cholera in the Democratic Republic of the Congo, 2000-2018: An eco-epidemiological study. PLoS Negl Trop Dis 2023; 17:e0011597. [PMID: 37639440 PMCID: PMC10491302 DOI: 10.1371/journal.pntd.0011597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 09/08/2023] [Accepted: 08/14/2023] [Indexed: 08/31/2023] Open
Abstract
BACKGROUND The dynamics of the spread of cholera epidemics in the Democratic Republic of the Congo (DRC), from east to west and within western DRC, have been extensively studied. However, the drivers of these spread processes remain unclear. We therefore sought to better understand the factors associated with these spread dynamics and their potential underlying mechanisms. METHODS In this eco-epidemiological study, we focused on the spread processes of cholera epidemics originating from the shores of Lake Kivu, involving the areas bordering Lake Kivu, the areas surrounding the lake areas, and the areas out of endemic eastern DRC (eastern and western non-endemic provinces). Over the period 2000-2018, we collected data on suspected cholera cases, and a set of several variables including types of conflicts, the number of internally displaced persons (IDPs), population density, transportation network density, and accessibility indicators. Using multivariate ordinal logistic regression models, we identified factors associated with the spread of cholera outside the endemic eastern DRC. We performed multivariate Vector Auto Regressive models to analyze potential underlying mechanisms involving the factors associated with these spread dynamics. Finally, we classified the affected health zones using hierarchical ascendant classification based on principal component analysis (PCA). FINDINGS The increase in the number of suspected cholera cases, the exacerbation of conflict events, and the number of IDPs in eastern endemic areas were associated with an increased risk of cholera spreading outside the endemic eastern provinces. We found that the increase in suspected cholera cases was influenced by the increase in battles at lag of 4 weeks, which were influenced by the violence against civilians with a 1-week lag. The violent conflict events influenced the increase in the number of IDPs 4 to 6 weeks later. Other influences and uni- or bidirectional causal links were observed between violent and non-violent conflicts, and between conflicts and IDPs. Hierarchical clustering on PCA identified three categories of affected health zones: densely populated urban areas with few but large and longer epidemics; moderately and accessible areas with more but small epidemics; less populated and less accessible areas with more and larger epidemics. CONCLUSION Our findings argue for monitoring conflict dynamics to predict the risk of geographic expansion of cholera in the DRC. They also suggest areas where interventions should be appropriately focused to build their resilience to the disease.
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Affiliation(s)
- Harry César Kayembe
- Department of Basic Sciences, Faculty of Medicine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
- Department of Environmental Sciences and Management, UR SPHERES, Faculty of Sciences, Université de Liège, Arlon, Belgium
| | - Didier Bompangue
- Department of Basic Sciences, Faculty of Medicine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
- Chrono-Environnement, UMR CNRS 6249, Université de Franche-Comté, Besançon, France
| | | | - Bien-Aimé Mandja
- Department of Basic Sciences, Faculty of Medicine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Doudou Batumbo
- Department of Basic Sciences, Faculty of Medicine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Muriel Matunga
- Graduate School Public Health Department, Adventist International Institute of Advanced Studies, Silang, Cavite, Philippines
| | - Jérémie Muwonga
- Department of Medical Biology, Faculty of Medicine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Michel Moutschen
- Department of Clinical Sciences, Immunopathology—Infectious Diseases and General Internal Medicine, Université de Liège, Liege, Belgium
| | - Hippolyte Situakibanza
- Department of Internal Medicine, Faculty of Medicine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
- Department of Parasitology and Tropical Medicine, Faculty of Medicine, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Pierre Ozer
- Department of Environmental Sciences and Management, UR SPHERES, Faculty of Sciences, Université de Liège, Arlon, Belgium
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Ouamba JP, Mbarga NF, Ciglenecki I, Ratnayake R, Tchiasso D, Finger F, Peyraud N, Mounchili I, Boyom T, Yonta C, Nwatchok L, Mouhamadou M, Ekedi C, Marcel J, Luquero F, Ekah F, Amani A, Tamakloe M, Boum Y, Esso L. Implementation of targeted cholera response activities, Cameroon. Bull World Health Organ 2023; 101:170-178. [PMID: 36865607 PMCID: PMC9948504 DOI: 10.2471/blt.22.288885] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 11/14/2022] [Accepted: 11/15/2022] [Indexed: 03/04/2023] Open
Abstract
Objective To describe the implementation of case-area targeted interventions to reduce cholera transmission using a rapid, localized response in Kribi district, Cameroon. Methods We used a cross-sectional design to study the implementation of case-area targeted interventions. We initiated interventions after rapid diagnostic test confirmation of a case of cholera. We targeted households within a 100-250 metre perimeter around the index case (spatial targeting). The interventions package included: health promotion, oral cholera vaccination, antibiotic chemoprophylaxis for nonimmunized direct contacts, point-of-use water treatment and active case-finding. Findings We implemented eight targeted intervention packages in four health areas of Kribi between 17 September 2020 and 16 October 2020. We visited 1533 households (range: 7-544 per case-area) hosting 5877 individuals (range: 7-1687 per case-area). The average time from detection of the index case to implementation of interventions was 3.4 days (range: 1-7). Oral cholera vaccination increased overall immunization coverage in Kribi from 49.2% (2771/5621 people) to 79.3% (4456/5621 people). Interventions also led to the detection and prompt management of eight suspected cases of cholera, five of whom had severe dehydration. Stool culture was positive for Vibrio cholerae O1 in four cases. The average time from onset of symptoms to admission of a person with cholera to a health facility was 1.2 days. Conclusion Despite challenges, we successfully implemented targeted interventions at the tail-end of a cholera epidemic, after which no further cases were reported in Kribi up until week 49 of 2021. The effectiveness of case-area targeted interventions in stopping or reducing cholera transmission needs further investigation.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Christine Ekedi
- Kribi District Hospital, Regional Delegation of the South, Kribi, Cameroon
| | - Johne Marcel
- Kribi District Hospital, Regional Delegation of the South, Kribi, Cameroon
| | | | - Faustin Ekah
- United Nations International Children's Emergency Fund, Yaounde, Cameroon
| | - Adidja Amani
- Sub-direction of Vaccination, Ministry of Public Health, Yaounde, Cameroon
| | | | | | - Linda Esso
- Department for the Control of Disease, Epidemics and Pandemics, Ministry of Public Health, Yaounde, Cameroon
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Tyhali A, Forbes PB. N − nitrosamines in surface and drinking waters: An African status report. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2022.116873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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George CM, Parvin T, Bhuyian MSI, Uddin IM, Zohura F, Masud J, Monira S, Sack DA, Perin J, Alam M, Faruque ASG. Randomized Controlled Trial of the Cholera-Hospital-Based-Intervention-for-7-Days (CHoBI7) Cholera Rapid Response Program to Reduce Diarrheal Diseases in Bangladesh. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:12905. [PMID: 36232205 PMCID: PMC9566036 DOI: 10.3390/ijerph191912905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/09/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
(a) Objective: To build an evidence base on effective water, sanitation, and hygiene interventions to reduce diarrheal diseases in cholera hotspots, we developed the CHoBI7 Cholera Rapid Response Program. (b) Methods: Once a cholera patient (confirmed by bacterial culture) is identified at a health facility, a health promoter delivers a targeted WASH intervention to the cholera hotspot (households within 20 m of a cholera patient) through both in-person visits during the first week and bi-weekly WASH mobile messages for the 3-month program period. A randomized controlled trial of the CHoBI7 Cholera Rapid Response Program was conducted with 284 participants in 15 cholera hotspots around cholera patients in urban Dhaka, Bangladesh. This program was compared to the standard message in Bangladesh on the use of oral rehydration solution for dehydration. Five-hour structured observation of handwashing with soap and diarrhea surveillance was conducted monthly. (c) Findings: Handwashing with soap at food- and stool-related events was significantly higher in the CHoBI7 Cholera Rapid Response Program arm compared to the standard message arm at all timepoints (overall 54% in the CHoBI7 arm vs. 23% in the standard arm, p < 0.05). Furthermore, there was a significant reduction in diarrheal prevalence for all participants (adults and children) (Prevalence Ratio (PR) 0.35, 95% CI: 0.14-0.85) and for children under 5 years of age (PR: 0.27, 95% CI: 0.085-0.87) during the 3-month program. (d) Conclusions: These findings demonstrate that the CHoBI7 Cholera Rapid Response Program is effective in lowering diarrhea prevalence and increasing handwashing with soap for a population at high risk of cholera.
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Affiliation(s)
- Christine Marie George
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205-2103, USA
| | - Tahmina Parvin
- Research Training and Management International, Dhaka 1216, Bangladesh
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
| | - Md. Sazzadul Islam Bhuyian
- Research Training and Management International, Dhaka 1216, Bangladesh
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
| | - Ismat Minhaj Uddin
- Research Training and Management International, Dhaka 1216, Bangladesh
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
| | - Fatema Zohura
- Research Training and Management International, Dhaka 1216, Bangladesh
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
| | - Jahed Masud
- Research Training and Management International, Dhaka 1216, Bangladesh
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
| | - Shirajum Monira
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
| | - David A. Sack
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205-2103, USA
| | - Jamie Perin
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205-2103, USA
| | - Munirul Alam
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
| | - A. S. G. Faruque
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka 1212, Bangladesh
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Ratnayake R, Peyraud N, Ciglenecki I, Gignoux E, Lightowler M, Azman AS, Gakima P, Ouamba JP, Sagara JA, Ndombe R, Mimbu N, Ascorra A, Welo PO, Mukamba Musenga E, Miwanda B, Boum Y, Checchi F, Edmunds WJ, Luquero F, Porten K, Finger F. Effectiveness of case-area targeted interventions including vaccination on the control of epidemic cholera: protocol for a prospective observational study. BMJ Open 2022; 12:e061206. [PMID: 35793924 PMCID: PMC9260795 DOI: 10.1136/bmjopen-2022-061206] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
INTRODUCTION Cholera outbreaks in fragile settings are prone to rapid expansion. Case-area targeted interventions (CATIs) have been proposed as a rapid and efficient response strategy to halt or substantially reduce the size of small outbreaks. CATI aims to deliver synergistic interventions (eg, water, sanitation, and hygiene interventions, vaccination, and antibiotic chemoprophylaxis) to households in a 100-250 m 'ring' around primary outbreak cases. METHODS AND ANALYSIS We report on a protocol for a prospective observational study of the effectiveness of CATI. Médecins Sans Frontières (MSF) plans to implement CATI in the Democratic Republic of the Congo (DRC), Cameroon, Niger and Zimbabwe. This study will run in parallel to each implementation. The primary outcome is the cumulative incidence of cholera in each CATI ring. CATI will be triggered immediately on notification of a case in a new area. As with most real-world interventions, there will be delays to response as the strategy is rolled out. We will compare the cumulative incidence among rings as a function of response delay, as a proxy for performance. Cross-sectional household surveys will measure population-based coverage. Cohort studies will measure effects on reducing incidence among household contacts and changes in antimicrobial resistance. ETHICS AND DISSEMINATION The ethics review boards of MSF and the London School of Hygiene and Tropical Medicine have approved a generic protocol. The DRC and Niger-specific versions have been approved by the respective national ethics review boards. Approvals are in process for Cameroon and Zimbabwe. The study findings will be disseminated to the networks of national cholera control actors and the Global Task Force for Cholera Control using meetings and policy briefs, to the scientific community using journal articles, and to communities via community meetings.
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Affiliation(s)
- Ruwan Ratnayake
- Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
- Epicentre, Paris, France
| | | | | | | | | | - Andrew S Azman
- Médecins Sans Frontières, Geneva, Switzerland
- Epidemiology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, Maryland, USA
| | | | | | | | | | | | | | - Placide Okitayemba Welo
- Programme National d'Elimination du Choléra et de lutte contre les autres Maladies Diarrhéiques, Kinshasa, Congo (the Democratic Republic of the)
| | | | - Berthe Miwanda
- Institut National de Recherche Biologique, Kinshasa, Congo (the Democratic Republic of the)
| | | | - Francesco Checchi
- Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - W John Edmunds
- Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - Francisco Luquero
- Epicentre, Paris, France
- GAVI the Vaccine Alliance, Geneva, Switzerland
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Meki CD, Ncube EJ, Voyi K. Community-level interventions for mitigating the risk of waterborne diarrheal diseases: a systematic review. Syst Rev 2022; 11:73. [PMID: 35436979 PMCID: PMC9016942 DOI: 10.1186/s13643-022-01947-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 04/05/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Waterborne diarrhea diseases are among the leading causes of morbidity and mortality globally. These diseases can be mitigated by implementing various interventions. We reviewed the literature to identify available interventions to mitigate the risk of waterborne diarrheal diseases. METHODS We conducted a systematic database review of CINAHL (Cumulative Index to Nursing and Allied Health Literature), PubMed, Web of Science Core Collection, Cochrane library, Scopus, African Index Medicus (AIM), and LILACS (Latin American and Caribbean Health Sciences Literature). Our search was limited to articles published between 2009 and 2020. We conducted the review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement checklist. The identified studies were qualitatively synthesized. RESULTS Our initial search returned 28 773 articles of which 56 studies met the inclusion criteria. The included studies reported interventions, including vaccines for rotavirus disease (monovalent, pentavalent, and Lanzhou lamb vaccine); enhanced water filtration for preventing cryptosporidiosis, Vi polysaccharide for typhoid; cholera 2-dose vaccines, water supply, water treatment and safe storage, household disinfection, and hygiene promotion for controlling cholera outbreaks. CONCLUSION We retrieved few studies on interventions against waterborne diarrheal diseases in low-income countries. Interventions must be specific to each type of waterborne diarrheal disease to be effective. Stakeholders must ensure collaboration in providing and implementing multiple interventions for the best outcomes. SYSTEMATIC REVIEW REGISTRATION PROSPERO CRD42020190411 .
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Affiliation(s)
- Chisala D Meki
- University of Zambia, School of Public Health, University of Zambia, P O. BOX 50110, Lusaka, Zambia. .,School of Health Systems and Public Health, University of Pretoria, Pretoria, South Africa.
| | - Esper J Ncube
- School of Health Systems and Public Health, University of Pretoria, Pretoria, South Africa.,Rand Water, Johannesburg, South Africa
| | - Kuku Voyi
- School of Health Systems and Public Health, University of Pretoria, Pretoria, South Africa
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9
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Mohd Faizal Ab Jalil, Hamidin N, Gunny AAN, Kamarudzaman AN, Gopinath SCB. Potential Risks Assessment of Trihalomethanes in Drinking Water Supply. J WATER CHEM TECHNO+ 2022. [DOI: 10.3103/s1063455x21060060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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10
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Sikder M, Altare C, Doocy S, Trowbridge D, Kaur G, Kaushal N, Lyles E, Lantagne D, Azman AS, Spiegel P. Case-area targeted preventive interventions to interrupt cholera transmission: Current implementation practices and lessons learned. PLoS Negl Trop Dis 2021; 15:e0010042. [PMID: 34919551 PMCID: PMC8719662 DOI: 10.1371/journal.pntd.0010042] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 12/31/2021] [Accepted: 12/01/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Cholera is a major cause of mortality and morbidity in low-resource and humanitarian settings. It is transmitted by fecal-oral route, and the infection risk is higher to those living in and near cholera cases. Rapid identification of cholera cases and implementation of measures to prevent subsequent transmission around cases may be an efficient strategy to reduce the size and scale of cholera outbreaks. METHODOLOGY/PRINCIPLE FINDINGS We investigated implementation of cholera case-area targeted interventions (CATIs) using systematic reviews and case studies. We identified 11 peer-reviewed and eight grey literature articles documenting CATIs and completed 30 key informant interviews in case studies in Democratic Republic of Congo, Haiti, Yemen, and Zimbabwe. We documented 15 outbreaks in 12 countries where CATIs were used. The team composition and the interventions varied, with water, sanitation, and hygiene interventions implemented more commonly than those of health. Alert systems triggering interventions were diverse ranging from suspected cholera cases to culture confirmed cases. Selection of high-risk households around the case household was inconsistent and ranged from only one case to approximately 100 surrounding households with different methods of selecting them. Coordination among actors and integration between sectors were consistently reported as challenging. Delays in sharing case information impeded rapid implementation of this approach, while evaluation of the effectiveness of interventions varied. CONCLUSIONS/SIGNIFICANCE CATIs appear effective in reducing cholera outbreaks, but there is limited and context specific evidence of their effectiveness in reducing the incidence of cholera cases and lack of guidance for their consistent implementation. We propose to 1) use uniform cholera case definitions considering a local capacity to trigger alert; 2) evaluate the effectiveness of individual or sets of interventions to interrupt cholera, and establish a set of evidence-based interventions; 3) establish criteria to select high-risk households; and 4) improve coordination and data sharing amongst actors and facilitate integration among sectors to strengthen CATI approaches in cholera outbreaks.
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Affiliation(s)
- Mustafa Sikder
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins Center for Humanitarian Health, Baltimore, Maryland, United States of America
| | - Chiara Altare
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins Center for Humanitarian Health, Baltimore, Maryland, United States of America
| | - Shannon Doocy
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins Center for Humanitarian Health, Baltimore, Maryland, United States of America
| | - Daniella Trowbridge
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins Center for Humanitarian Health, Baltimore, Maryland, United States of America
| | - Gurpreet Kaur
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins Center for Humanitarian Health, Baltimore, Maryland, United States of America
| | - Natasha Kaushal
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins Center for Humanitarian Health, Baltimore, Maryland, United States of America
| | - Emily Lyles
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins Center for Humanitarian Health, Baltimore, Maryland, United States of America
| | - Daniele Lantagne
- Consultant, Public Health Engineer, Boston, Massachusetts, United States of America
| | - Andrew S. Azman
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins Center for Humanitarian Health, Baltimore, Maryland, United States of America
| | - Paul Spiegel
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- Johns Hopkins Center for Humanitarian Health, Baltimore, Maryland, United States of America
- * E-mail:
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11
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D'Mello-Guyett L, Cumming O, Bonneville S, D'hondt R, Mashako M, Nakoka B, Gorski A, Verheyen D, Van den Bergh R, Welo PO, Maes P, Checchi F. Effectiveness of hygiene kit distribution to reduce cholera transmission in Kasaï-Oriental, Democratic Republic of Congo, 2018: a prospective cohort study. BMJ Open 2021; 11:e050943. [PMID: 34649847 PMCID: PMC8522665 DOI: 10.1136/bmjopen-2021-050943] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
INTRODUCTION Household contacts of cholera cases are at a greater risk of Vibrio cholerae infection than the general population. There is currently no agreed standard of care for household contacts, despite their high risk of infection, in cholera response strategies. In 2018, hygiene kit distribution and health promotion was recommended by Médecins Sans Frontières for admitted patients and accompanying household members on admission to a cholera treatment unit in the Democratic Republic of Congo. METHODS To investigate the effectiveness of the intervention and risk factors for cholera infection, we conducted a prospective cohort study and followed household contacts for 7 days after patient admission. Clinical surveillance among household contacts was based on self-reported symptoms of cholera and diarrhoea, and environmental surveillance through the collection and analysis of food and water samples. RESULTS From 94 eligible households, 469 household contacts were enrolled and 444 completed follow-up. Multivariate analysis suggested evidence of a dose-response relationship with increased kit use associated with decreased relative risk of suspected cholera: household contacts in the high kit-use group had a 66% lower incidence of suspected cholera (adjusted risk ratio (aRR) 0.34, 95% CI 0.11 to 1.03, p=0.055), the mid-use group had a 53% lower incidence (aRR 0.47, 95% CI 0.17 to 1.29, p=1.44) and low-use group had 22% lower incidence (aRR 0.78, 95% CI 0.24 to 2.53, p=0.684), compared with household contacts without a kit. Drinking water contamination was significantly reduced among households in receipt of a kit. There was no significant effect on self-reported diarrhoea or food contamination. CONCLUSION The integration of a hygiene kit intervention to case-households may be effective in reducing cholera transmission among household contacts and environmental contamination within the household. Further work is required to evaluate whether other proactive localised distribution among patients and case-households or to households surrounding cholera cases can be used in future cholera response programmes in emergency contexts.
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Affiliation(s)
- Lauren D'Mello-Guyett
- London School of Hygiene & Tropical Medicine, London, UK
- Médecins Sans Frontières, Brussels, Belgium
| | - Oliver Cumming
- London School of Hygiene & Tropical Medicine, London, UK
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12
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Bwire G, Waniaye JB, Otim JS, Matseketse D, Kagirita A, Orach CG. Cholera risk in cities in Uganda: understanding cases and contacts centered strategy (3CS) for rapid cholera outbreak control. Pan Afr Med J 2021; 39:193. [PMID: 34603574 PMCID: PMC8464210 DOI: 10.11604/pamj.2021.39.193.27794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Accepted: 06/26/2021] [Indexed: 11/15/2022] Open
Abstract
Introduction in the recent past, cities in sub-Saharan Africa have reported serious cholera outbreaks that last for several months. Uganda is one of the African countries where cities are prone to cholera outbreaks. Studies on cholera in Bangladesh show increased risk of cholera for the immediate household members (contacts) yet the control interventions mainly target cases with little or no focus on contacts. This study aimed to describe the rapid control of cholera outbreaks in Kampala and Mbale cities, Uganda, using, “Cases and Contacts Centered Strategy (3CS)” that consisted of identification and treatment of cases, promotion of safe water, sanitation, hygiene (WaSH) and selective chemoprophylaxis for the contacts. Methods a cross-sectional study was conducted in 2015-2016 in the Kampala and Mbale cities during cholera outbreaks. Cholera cases were treated and 816 contacts from 188 households were listed and given cholera preventive packages. Data were collected, cleaned, analysed and stored in spreadsheet. Comparison of categories was done using Chi-Square test. Results a total of 58 and 41 confirmed cholera cases out of 318 and 153 suspected cases were recorded in Kampala and Mbale cities respectively. The outbreaks lasted for 41 days in both cities. Case fatality rates were high; 12.1% (5/41) for Mbale city and 1.7% (1/58) for Kampala city. Fifty-five percent (210/379) of stool samples were tested by culture to confirm V. choleraeO1. No contacts listed and given cholera preventive package developed cholera. Both sexes and all age groups were affected. In Kampala city, the males were more affected than the females in the age groups less than 14 years, p-value of 0.0097. Conclusion this study showed that by implementing 3CS, it was possible to rapidly control cholera outbreaks in Kampala and Mbale cities and no cholera cases were reported amongst the listed household contacts. The findings on 3CS and specifically, selective antibiotic chemoprophylaxis for cholera prevention, could be used in similar manner to oral cholera vaccines to complement the core cholera control interventions (disease surveillance, treatment of cases and WaSH). However, studies are needed to guide such rollout and to understand the age-sex differences in Kampala city.
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Affiliation(s)
- Godfrey Bwire
- Department of Integrated Epidemiology, Surveillance and Public Health Emergencies, Ministry of Health, Kampala, Uganda
| | | | - Julius Simon Otim
- Directorate of Public Health, Kampala Capital City Authority, Kampala, Uganda
| | | | - Atek Kagirita
- Uganda National Health Laboratory Services/Central Public Health Laboratories, Ministry of Health, Kampala, Uganda
| | - Christopher Garimoi Orach
- Department of Community Health and Behavioral Sciences, Makerere University College of Health Sciences, School of Public Health, Kampala, Uganda
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13
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Ratnayake R, Finger F, Edmunds WJ, Checchi F. Early detection of cholera epidemics to support control in fragile states: estimation of delays and potential epidemic sizes. BMC Med 2020; 18:397. [PMID: 33317544 PMCID: PMC7737284 DOI: 10.1186/s12916-020-01865-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Accepted: 11/23/2020] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Cholera epidemics continue to challenge disease control, particularly in fragile and conflict-affected states. Rapid detection and response to small cholera clusters is key for efficient control before an epidemic propagates. To understand the capacity for early response in fragile states, we investigated delays in outbreak detection, investigation, response, and laboratory confirmation, and we estimated epidemic sizes. We assessed predictors of delays, and annual changes in response time. METHODS We compiled a list of cholera outbreaks in fragile and conflict-affected states from 2008 to 2019. We searched for peer-reviewed articles and epidemiological reports. We evaluated delays from the dates of symptom onset of the primary case, and the earliest dates of outbreak detection, investigation, response, and confirmation. Information on how the outbreak was alerted was summarized. A branching process model was used to estimate epidemic size at each delay. Regression models were used to investigate the association between predictors and delays to response. RESULTS Seventy-six outbreaks from 34 countries were included. Median delays spanned 1-2 weeks: from symptom onset of the primary case to presentation at the health facility (5 days, IQR 5-5), detection (5 days, IQR 5-6), investigation (7 days, IQR 5.8-13.3), response (10 days, IQR 7-18), and confirmation (11 days, IQR 7-16). In the model simulation, the median delay to response (10 days) with 3 seed cases led to a median epidemic size of 12 cases (upper range, 47) and 8% of outbreaks ≥ 20 cases (increasing to 32% with a 30-day delay to response). Increased outbreak size at detection (10 seed cases) and a 10-day median delay to response resulted in an epidemic size of 34 cases (upper range 67 cases) and < 1% of outbreaks < 20 cases. We estimated an annual global decrease in delay to response of 5.2% (95% CI 0.5-9.6, p = 0.03). Outbreaks signaled by immediate alerts were associated with a reduction in delay to response of 39.3% (95% CI 5.7-61.0, p = 0.03). CONCLUSIONS From 2008 to 2019, median delays from symptom onset of the primary case to case presentation and to response were 5 days and 10 days, respectively. Our model simulations suggest that depending on the outbreak size (3 versus 10 seed cases), in 8 to 99% of scenarios, a 10-day delay to response would result in large clusters that would be difficult to contain. Improving the delay to response involves rethinking the integration at local levels of event-based detection, rapid diagnostic testing for cluster validation, and integrated alert, investigation, and response.
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Affiliation(s)
- Ruwan Ratnayake
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK. .,Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, London, UK. .,Health in Humanitarian Crises Centre, London School of Hygiene and Tropical Medicine, London, UK.
| | | | - W John Edmunds
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.,Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene and Tropical Medicine, London, UK.,Health in Humanitarian Crises Centre, London School of Hygiene and Tropical Medicine, London, UK
| | - Francesco Checchi
- Department of Infectious Disease Epidemiology, Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.,Health in Humanitarian Crises Centre, London School of Hygiene and Tropical Medicine, London, UK
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14
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Ratnayake R, Finger F, Azman AS, Lantagne D, Funk S, Edmunds WJ, Checchi F. Highly targeted spatiotemporal interventions against cholera epidemics, 2000-19: a scoping review. THE LANCET. INFECTIOUS DISEASES 2020; 21:e37-e48. [PMID: 33096017 DOI: 10.1016/s1473-3099(20)30479-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/27/2020] [Accepted: 05/19/2020] [Indexed: 01/12/2023]
Abstract
Globally, cholera epidemics continue to challenge disease control. Although mass campaigns covering large populations are commonly used to control cholera, spatial targeting of case households and their radius is emerging as a potentially efficient strategy. We did a Scoping Review to investigate the effectiveness of interventions delivered through case-area targeted intervention, its optimal spatiotemporal scale, and its effectiveness in reducing transmission. 53 articles were retrieved. We found that antibiotic chemoprophylaxis, point-of-use water treatment, and hygiene promotion can rapidly reduce household transmission, and single-dose vaccination can extend the duration of protection within the radius of households. Evidence supports a high-risk spatiotemporal zone of 100 m around case households, for 7 days. Two evaluations separately showed reductions in household transmission when targeting case households, and in size and duration of case clusters when targeting radii. Although case-area targeted intervention shows promise for outbreak control, it is critically dependent on early detection capacity and requires prospective evaluation of intervention packages.
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Affiliation(s)
- Ruwan Ratnayake
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK; Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London, UK.
| | | | - Andrew S Azman
- Department of Epidemiology and Center for Humanitarian Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Médecins Sans Frontières, Geneva, Switzerland
| | - Daniele Lantagne
- Department of Civil and Environmental Engineering, Tufts University, Medford, MA, USA
| | - Sebastian Funk
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - W John Edmunds
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK; Centre for the Mathematical Modelling of Infectious Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Francesco Checchi
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
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D'Mello-Guyett L, Greenland K, Bonneville S, D'hondt R, Mashako M, Gorski A, Verheyen D, Van den Bergh R, Maes P, Checchi F, Cumming O. Distribution of hygiene kits during a cholera outbreak in Kasaï-Oriental, Democratic Republic of Congo: a process evaluation. Confl Health 2020; 14:51. [PMID: 32760439 PMCID: PMC7379792 DOI: 10.1186/s13031-020-00294-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 07/15/2020] [Indexed: 12/30/2022] Open
Abstract
Background Cholera remains a leading cause of infectious disease outbreaks globally, and a major public health threat in complex emergencies. Hygiene kits distributed to cholera case-households have previously shown an effect in reducing cholera incidence and are recommended by Médecins Sans Frontières (MSF) for distribution to admitted patients and accompanying household members upon admission to health care facilities (HCFs). Methods This process evaluation documented the implementation, participant response and context of hygiene kit distribution by MSF during a 2018 cholera outbreak in Kasaï-Oriental, Democratic Republic of Congo (DRC). The study population comprised key informant interviews with seven MSF staff, 17 staff from other organisations and a random sample of 27 hygiene kit recipients. Structured observations were conducted of hygiene kit demonstrations and health promotion, and programme reports were analysed to triangulate data. Results and conclusions Between Week (W) 28-48 of the 2018 cholera outbreak in Kasaï-Oriental, there were 667 suspected cholera cases with a 5% case fatality rate (CFR). Across seven HCFs supported by MSF, 196 patients were admitted with suspected cholera between W43-W47 and hygiene kit were provided to patients upon admission and health promotion at the HCF was conducted to accompanying household contacts 5-6 times per day. Distribution of hygiene kits was limited and only 52% of admitted suspected cholera cases received a hygiene kit. The delay of the overall response, delayed supply and insufficient quantities of hygiene kits available limited the coverage and utility of the hygiene kits, and may have diminished the effectiveness of the intervention. The integration of a WASH intervention for cholera control at the point of patient admission is a growing trend and promising intervention for case-targeted cholera responses. However, the barriers identified in this study warrant consideration in subsequent cholera responses and further research is required to identify ways to improve implementation and delivery of this intervention.
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Affiliation(s)
- Lauren D'Mello-Guyett
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.,Environmental Health Unit, Médecins Sans Frontières, Brussels, Belgium
| | - Katie Greenland
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
| | | | - Rob D'hondt
- Environmental Health Unit, Médecins Sans Frontières, Brussels, Belgium
| | - Maria Mashako
- Médecins Sans Frontières, Kinshasa, Democratic Republic of Congo
| | - Alexandre Gorski
- Médecins Sans Frontières, Kinshasa, Democratic Republic of Congo
| | - Dorien Verheyen
- Médecins Sans Frontières, Kinshasa, Democratic Republic of Congo
| | - Rafael Van den Bergh
- LuxOR, Luxembourg Operational Research Unit, Médecins Sans Frontières, Luxembourg City, Luxembourg
| | - Peter Maes
- Environmental Health Unit, Médecins Sans Frontières, Brussels, Belgium
| | - Francesco Checchi
- Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK
| | - Oliver Cumming
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK
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