Can improved handwashing infrastructure and soap change behavior? findings from a randomized control study in the...

Globally, around 40% of people lack access to handwashing facilities with soap and water, a proportion likely higher in crisis-affected settings such as refugee camps. This increases vulnerability to hygiene-related diseases including diarrhea and respiratory infections. This study assessed whether improved access to handwashing facilities (Jengu) increases handwashing with soap (HWWS) among refugees in Dadaab camp, Kenya. Jengu is a foot-operated handwashing facility which is designed to integrate water storage, soap placement, and drainage in a compact structure suitable for household use in resource-constrained environments.

A randomized control study was conducted in Dadaab refugee camp in Kenya between June 2023 to July 2024. The sample size was 300 households across nine camp sections. Households were randomly assigned to receive either an intervention group receiving a Jengu handwashing facility with a 20-L jerry can and regular soap supply (n = 150) or a control group receiving soap provision only (n = 150). Soap was distributed bi-monthly to both groups. Data were collected through structured observations and household surveys at baseline, one-month post-intervention, and endline. Surveys assessed sociodemographic factors, knowledge, attitudes, and practices, while observations captured HWWS behavior at predefined critical hygiene moments. Descriptive statistics summarized baseline data. Logistic regression and a difference-in-differences approach were used to evaluate predictors and intervention effects.

Among respondents, 75.4% were female (mean age 42 ± 12.7 years), 62.3% of household heads had no formal education. Across all rounds, 4,323 critical handwashing events were observed, of which 38.5% involved HWWS. HWWS prevalence rose from 28.4% at baseline to 61.0% one-month post-intervention, then declined to 32.4% at endline, remaining above baseline. Total HWWS moments nearly doubled (350 to 597), with the largest relative increase before child feeding (sixfold rise). HWWS before eating was significantly greater in the intervention group at endline (OR = 1.77, 95% CI: 1.13-2.77, p = 0.013). Soap and water availability were key predictors, HWWS odds were 2.53 times higher with soap (95% CI: 2.08-3.06, p < 0.001) and 1.23 times higher with water (95% CI: 1.02-1.49, p = 0.027). Compared to baseline, HWWS odds tripled at one month(OR = 3.05, 95% CI: 2.47-3.73, p < 0.001) and remained elevated at endline (OR = 1.20, 95% CI: 1.01-1.42, p = 0.037).

Enhanced handwashing facilities, consistent soap provision, and improved water access substantially increased HWWS in this refugee setting. Soap availability was critical for sustaining behaviors, while the Jengu facility prompted short-term gains. Integrated WASH interventions combining infrastructure, supply continuity, and behavior change strategies are essential for lasting hygiene improvements in humanitarian contexts.