Effect of Drinking Water Chlorination on Child Survival in Rural Kenya

The World Health Organization (WHO) estimates that in 2015 over 2 billion people consumed drinking water contaminated with feces and that approximately half a million people died from diarrheal disease associated with fecal contamination of water (1). Dilute chlorine solution is widely used to treat water as it is effective, safe, and low-cost. While nonexperimental studies suggest strong impacts of chlorine water treatment on child survival (2-4), there has been no previous randomized controlled trial of a water treatment intervention powered to evaluate effects on child survival.

We will examine the effect of community-wide provision of chlorine solution on child survival in rural Kenya, where a long-term village-wide chlorination randomized evaluation was implemented. The WASH Benefits Kenya trial was a randomized controlled trial of water treatment, sanitation, handwashing, and nutrition interventions in western Kenya. WASH Benefits Kenya enrolled pregnant women in their second or third gestational trimester between November 2012 and May 2014 and followed children for their first 2 years of life. In communities that were randomized to water treatment, chlorine solution dispensers were installed and refilled as needed. After the WASH Benefits Kenya trial ended, the NGO Evidence Action continued to refill most of the dispensers in the treatment villages.

We intend to re-visit all water treatment and control clusters in the trial approximately 6 years after the chlorination intervention was initiated to enroll all women 50 or younger, who had a child since January 1, 2008. We note that our target population includes both women (and children) who were and who were not "enrolled" in the original WASH Benefits Kenya study. The latter group is made up of women (and their children) who were pregnant before the study, women who were in their first trimester at the time of enrollment, and women who got pregnant after study enrollment. We expect to find approximately 22,000 such women. We will briefly survey these women to identify those that gave birth to a child who later died, and then conduct verbal autopsies to ascertain the cause of death. We will also perform free and total chlorine residual testing at households to assess current usage rates and collect GPS data on the location of houses and dispensers. We will estimate the intent-to-treat effect of the community-wide provision of chlorine solution on child survival by 1) comparing post-intervention mortality rates between water treatment and control areas; and 2) comparing changes in mortality rates (before and after the intervention) across treatment and control areas (a difference-in-difference analysis). The primary outcomes are all-cause child mortality and infectious disease related child mortality; secondary outcomes include: 7-day diarrhea prevalence, all-cause under-2 mortality, diarrheal disease related child mortality, school attendance, and school enrollment. In addition, for the subsample of children who were enrolled in the original WASH Benefits Kenya study, we will examine effects on motor development, emergent language and literacy, emergent math/numeracy, and socio-emotional development. Our findings will provide evidence on whether community-wide provision of chlorine reduces all-cause child mortality and infectious disease related child mortality.