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Abstract Progress toward achieving Sustainable Development Goal 6, clean water and sanitation for all, is behind schedule and faces substantial financial challenges. Rigorous water, sanitation, and hygiene (WASH) interventions have underperformed, casting doubt on their efficacy and potentially undermining confidence in WASH funding and investments. But these interventions have leaned on a narrow set of WASH indicators—linear growth and diarrhea—that reflect a 20th‐century prioritization of microbiological water quality as the most important measurement of WASH intervention success. Even when water is microbiologically safe, hundreds of millions of people face harassment, assault, injury, poisoning, anxiety, exhaustion, depression, social exclusion, discrimination, subjugation, hunger, debt, or work, school, or family care absenteeism when retrieving or consuming household water. Measures of WASH intervention success should incorporate these impacts to reinforce the WASH value proposition. We present a way forward for implementing a monitoring and evaluation paradigm shift that can help achieve transformative WASH. This article is categorized under:Engineering Water > Water, Health, and SanitationHuman Water > Value of WaterHuman Water > Methods
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Impact of a multi-pronged cholera intervention in an endemic setting
Abstract Cholera is a bacterial water-borne diarrheal disease transmitted via the fecal-oral route that causes high morbidity in sub-Saharan Africa and Asia. It is preventable with vaccination, and Water, Sanitation, and Hygiene (WASH) improvements. However, the impact of vaccination in endemic settings remains unclear. Cholera is endemic in the city of Kalemie, on the shore of Lake Tanganyika, in the Democratic Republic of Congo, where both seasonal mobility and the lake, a potential environmental reservoir, may promote transmission. Kalemie received a vaccination campaign and WASH improvements in 2013-2016. We assessed the impact of this intervention to inform future control strategies in endemic settings. We fit compartmental models considering seasonal mobility and environmentally-based transmission. We estimated the number of cases the intervention avoided, and the relative contributions of the elements promoting local cholera transmission. We estimated the intervention avoided 5,259 cases (95% credible interval: 1,576.6-11,337.8) over 118 weeks. Transmission did not rely on seasonal mobility and was primarily environmentally-driven. Removing environmental exposure or contamination could control local transmission. Repeated environmental exposure could maintain high population immunity and decrease the impact of vaccination in similar endemic areas. Addressing environmental exposure and contamination should be the primary target of interventions in such settings. Author summaryCholera is a major global health concern that causes high morbidity. It is a bacterial water-borne disease that can be transmitted via the fecal-oral route or the ingestion of contaminated water. Hence, both population mobility and environmental exposure can promote cholera persistence. The primary tools to prevent cholera include vaccination and Water, Sanitation, and Hygiene (WASH) improvements. The effectiveness of these interventions is well understood in epidemic settings, but their impact in endemic settings is unclear. Achieving cholera elimination requires disentangling the contributors to transmission, specifically population mobility and aquatic reservoirs, and assessing the impact of interventions performed in endemic settings.This study focuses on Kalemie, a cholera endemic city in the Democratic Republic of Congo, on shore of a lake that serves as a potential environmental reservoir. It quantifies the short-term impact of an intervention that used targeted vaccination and WASH. The study shows that the impact of vaccination was dampened by very high background immunity due to constant environmental exposure. This suggests that WASH improvements should be the primary intervention in such settings despite the time- and resource-intensive nature of implementation.
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- Award ID(s):
- 2015273
- PAR ID:
- 10560799
- Publisher / Repository:
- medRxiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- medRxiv
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Posted Content:
- https://doi.org/10.1101/2023.12.14.23299970
