Estimating effectiveness of case-area targeted response interventions against cholera in Haiti
Abstract
Case-area targeted interventions (CATIs) against cholera are conducted by rapid response teams, and may include various activities like water, sanitation, hygiene measures. However, their real-world effectiveness has never been established. We conducted a retrospective observational study in 2015-2017 in the Centre department of Haiti. Using cholera cases, stool cultures and CATI records, we identified 238 outbreaks that were responded to. After adjusting for potential confounders, we found that a prompt response could reduce the number of accumulated cases by 76% (95% confidence interval, 59 to 86) and the outbreak duration by 61% (41 to 75) when compared to a delayed response. An intense response could reduce the number of accumulated cases by 59% (11 to 81) and the outbreak duration by 73% (49 to 86) when compared to a weaker response. These results suggest that prompt and repeated CATIs were significantly effective at mitigating and shortening cholera outbreaks in Haiti.
Data availability
Data generated or analysed during this study are included in the manuscript and supporting files.Source data files have been provided for Figures 1 and 4.
Article and author information
Author details
Funding
UNICEF
- Samuel Beaulieu
- Gregory Bulit
- Stanislas Rebaudet
Assistance Publique - Hopitaux de Marseille
- Stanislas Rebaudet
Assistance Publique - Hopitaux de Paris
- Renaud Piarroux
The funders of this study (UNICEF, APHM, APHP) had staff (co-authors of this manuscript) who had a role in data collection, analyses and writing of the report. However, the funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Ethics
Human subjects: All analyses retrospectively included routinely collected cholera surveillance and control data. The study protocol received authorization #1718-24 from the National Bioethics Committee of Haiti MSPP. The study only analysed anonymised data. Informed consent from patients and from people who benefited from a response intervention was therefore not required for this study.
Copyright
© 2019, Michel et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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