The role of water, sanitation and hygiene interventions in reducing soil-transmitted helminths: interpreting the evidence and identifying next steps

• Type of Material: Article
• Authors: Susana Vaz Nery, University of New South Wales; Amy J. Pickering, Tufts University; Ebba Abate, Ethiopian Public Health Institute; Abraham Asmare, World Vision Ethiopia; Laura Barrett, Children’s Investment Fund Foundation; Jade Benjamin-Chung, University of California, Berkeley; Donald A. P. Bundy, London School of Hygiene & Tropical Medicine; Thomas Clasen, Emory University; Archie C.A. Clements, Curtin University; John M. Colford Jr., University of California, Berkeley; Ayse Ercumen, University of California, Berkeley; Siobhan Crowley, Children’s Investment Fund Foundation; Oliver Cumming, London School of Hygiene & Tropical Medicine; Matthew Freeman, Emory University; Rashidul Haque, International Centre for Diarrheal Disease Research; Birhan Mengistu, Federal Ministry of Health; William E. Oswald, London School of Hygiene & Tropical Medicine; Rachel L. Pullan, London School of Hygiene & Tropical Medicine; Rita G. Oliveira, Children’s Investment Fund Foundation; Katey Einterz Owen, Bill & Melinda Gates Foundation
• Language: English
• Date: 2019-05-28
• Publisher: BMC (part of Springer Nature)
• Publication Version: Final Published Version
• Copyright Statement: © 2019 The Author(s).
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1186/s13071-019-3532-6
• Title of Journal or Parent Work: Parasites and Vectors
• ISSN: 1756-3305
• Volume: 12
• Issue: 1
• Start Page: 273
• End Page: 273
• Grant/Funding Information: The meeting was organized and supported by Bill & Melinda Gates Foundation and the Children’s Investment Fund Foundation.
• Keywords: Water; Life Sciences & Biomedicine; Soil-transmitted helminths; Sanitation; Science & Technology; REINFECTION; WASH; Tropical Medicine; Hygiene; Parasitology; IMPACT; INFECTIONS
• Research Categories: Environmental Sciences; Biology, Parasitology; Health Sciences, Public Health

Abstract

The transmission soil transmitted helminths (STH) occurs via ingestion of or contact with infective stages present in soil contaminated with human faeces. It follows therefore that efforts to reduce faecal contamination of the environment should help to reduce risk of parasite exposure and improvements in water, sanitation and hygiene (WASH) are seen as essential for the long-term, sustainable control of STH. However, the link between WASH and STH is not always supported by the available evidence from randomised controlled trials, which report mixed effects of WASH intervention on infection risk. This review critically summarises the available trial evidence and offers an interpretation of the observed heterogeneity in findings. The review also discusses the implications of findings for control programmes and highlights three main issues which merit further consideration: intervention design, exposure assessment, and intervention fidelity assessment.