An increasing number of people are affected by natural disasters, disease outbreaks and conflict. Water, sanitation and hygiene (WASH) interventions are used in nearly all emergency contexts to help reduce the risk of disease by providing safe water, reducing open defecation and promoting hygiene practices. However, evidence to support emergency WASH interventions is limited, forcing responders to rely on past experiences or extrapolated evidence from development settings.
The objective of this review was to assess the outcomes and impacts of short-term emergency WASH interventions in low- and middle-income countries (L&MICs).
Specific research objectives were aimed at addressing five knowledge gaps in emergency WASH interventions: 1. What are the effects of the use of services in emergency WASH situations? 2. What are the health-related outcomes in emergency WASH situations? 3. What are the non-health-related outcomes in emergency WASH interventions? 4. What contextual factors act as barriers or facilitators to implementation and uptake and the effectiveness in emergency WASH situations? 5. What is the cost-effectiveness of emergency WASH interventions?
The review uses a systematic review process to capture the available research in the emergency WASH sector from published and unpublished 'grey' literature. They searched sources of published and grey literature including academic databases, such as'Cochrane Library, Google Scholar, IDEAS, LILACs, Ovid Medline (Pubmed), Scopus, and Web of Science, and directly solicited studies. The scope of the review covers studies on populations affected by an emergency in a low or middle-income country and published between 1995 - 2016. The review includes both quantitative and qualitative studies. Authors' independently screened results by title, then abstract and full text. Authors also undertook independent data extraction and a risk'of bias analysis for inlcuded studies. The authors grouped results by intervention and summarized findings based on reported outcomes through narrative synthesis.
Headline Findings: a summary statement
There is'evidence supporting that 12 out of the 13 interventions included in the review do improve WASH conditions,'and therefore in theory reduce'the risk of disease transmission, but there is only limited evidence to support this second step. The effective interventions include water dipensers, household water treatment, constructing latrines, providing alternatives to latrines, and hygiene promotion. There is, however, clear evidence against pumping wells flooded with seawater.
The review includes 106 studies covering'114 unique evaluations. It includes interventions from 39 different countries in East Asia and Pacific (including South East Asia), South Asia, Middle East and North Africa, Sub-Saharan Africa, Latin America and the Caribbean. The review identifies, and includes, 13 specific interventions, including water source treatments, household water treatment, sanitation, hygiene promotion and environmental hygiene.
Implications for policy and practice
The authors find the emergency intervention can be improved by having a better understanding of previous development projects and the local social influences, which can effect the preferences of the poulattion.'The technical efficacy of WASH interventions has'generally been established, but creating effective and rapid behaviour change, such as that needed in an emergency context, remains a primary hurdle. Practitioners should try to collect consistent indicators to facilitate the comparison of grey literature reports.
Implications for further research
Additional evidence is needed for interventions, such as bucket chlorination, bulk water treatment, handwashing, household spraying, water trucking, and environmental clean-up,'as well as'formal economic analysis of all WASH interventions. Evaluation methodologies that require significant time and resources, such as randomised controlled trials, are not always appropriate or necessary for emergency WASH interventions. Non-experimental evaluations with consistent methods can provide sufficient evidence across emergency settings.
Programmes involving multiple WASH interventions simultaneously are commonly carried out by responders to emergencies, however, these are complex and difficult to research. Complex evaluation strategies, which help investigate synergies and spillover impacts,'are needed.
Numerous best practice and guidance documents are available from UN agencies, donors and responding organisations, but they are often contradictory. An analysis to identify inconsistencies and consolidate what is considered best practice and what is evidence-based is needed to align best practice across the sector.
This review is of a high quality. No strong conclusions were drawn for policy or practice.