Effect of water, sanitation, and hygiene on childhood growth in Ethiopia: a cluster-randomized trial

Background: Child growth faltering contributes significantly to global morbidity and mortality, with a disproportionate impact on low- and middle-income countries. Poor quality water, sanitation, and hygiene (WASH) has been identified as a risk factor, though prior studies have found mixed evidence for the effectiveness of WASH interventions. Methods: The WASH Upgrades for Health in Amhara (WUHA) trial was a two-arm, parallel-group, cluster-randomized trial carried out in three districts of the Wag Hemra Zone of Amhara from 2016 – 2019 (ClinicalTrials.gov #NCT02754583). The intervention consisted of hygiene infrastructure improvements and hygiene promotion at the household, community, and school level. Height and weight were pre-specified secondary outcomes that were measured annually in the longitudinal cohort of children aged 0–5 years at baseline. Results: Twenty communities were randomized to the WASH intervention and 20 to the control (delayed WASH) arm. Anthropometric measurements were done at baseline for a random sample of 613 children in the WASH intervention arm and 644 children in the control arm. There was no statistically significant difference over the 3-year study period for either height (0.1 cm lower in the WASH arm, 95%CI −0.5 to 0.2, P=0.45) or weight (0.02 kg higher in the WASH arm, 95%CI −0.06 to 0.10, P=0.64). Conclusions: A comprehensive WASH intervention implemented for three years in rural Ethiopia did not improve growth among children 0–5 years old.