An excellent review by colleagues at Tufts. They reviewed some 15,000 relevant documents.

Yates et al. 2018. Water, sanitation, and hygiene interventions in outbreak response: a synthesis of evidence. Waterlines 37(1):5-30. Practical Action Publishing.

www.developmentbookshelf.com/doi/pdf/10....5OR5R,GWCQAS,M4SV2,1

From the paper:

"We found that WASH interventions consistently reduced both the risk of disease and the risk of transmission in outbreak contexts; however, programme design and beneficiary preferences were important considerations to ensure WASH intervention effectiveness.
Critical programme design characteristics included simple interventions that were appropriately timed, community-driven, and had linkages between relief and development. Beneficiary preferences, barriers, and facilitators to WASH interventions in outbreak response were taste and smell of water treatment, communication methods, inaccurate perception of efficacy, and trust/fear."

Regards