Targeting WASH to those living near diarrhea patients offers a cost-effective approach to reduce diarrhea outbreaks by reaching those at highest risk. This contrasts the traditional “blanket approach,” which waits for large outbreaks before deploying broad, in-person interventions that are costly and time-consuming. mHealth messaging provides a low-cost, scalable method to alert communities to public health threats without the need for resource-intensive visits. This is particularly important given the global funding crisis for WASH interventions and development.

WASHmobile targets high-risk populations for diarrhea and diarrhea outbreaks. This program is healthcare facility initiated with an alert of a diarrhea patient and/or diarrhea outbreak. In the healthcare facility a promoter delivers a WASH module and WASH kit to diarrhea patients. WASHmobile voice and SMS messages are then sent from a doctor at a local hospital to diarrhea patient households and to those in the community where diarrhea outbreaks are occurring. Chlorine e-vouchers are also sent by SMS to these households to redeem chlorine tablets for free at local shops and pharmacies to increase chlorination behaviors.

Key preconditions include:

• Partnership with mobile network operators to send location-based push notifications as voice calls and SMS messages

• Basic mobile network coverage in the target area to ensure participants can receive voice calls and SMS messages (cellular internet is not needed)

• A mobile messaging platform to automate delivery of WASHmobile voice calls and SMS messages (drip campaigns), such as engageSPARK

• Partnership with the Ministry of Health or a local health authority to identify high-risk households for diarrhea through healthcare facility diarrhea case surveillance

We recommend starting by reviewing our Operational Guide and the Resources page to better understand how to implement WASHmobile, as well as reviewing the full the FAQ section.

E-vouchers are digital coupons sent by SMS that allow participants to redeem essential WASH products—such as chlorine tablets or soap—free of charge. Each voucher includes a unique code that can be validated by a participating shop or pharmacy using an SMS shortcode (no internet required). Once the e-voucher is used, the code is automatically marked as redeemed. This system makes it easy and secure for households and vendors to use WASH e-vouchers. In WASHmobile, both diarrhea patient households and those in diarrhea outbreak areas receive e-vouchers for chlorine tablets.