School of Public Health

Kristen Heitzinger

Strategies for the Promotion of Household Water Treatment in Ica, Peru

Boiling is the most common method of household water treatment in low- and middle-income countries, however, it is not always effectively practiced. We examined factors associated with Escherichia coli contamination of improved water supplies among 207 households in a rural population in Peru that practiced boiling. We subsequently conducted a randomized controlled trial among these households to assess the effectiveness of water pasteurization and safe storage interventions in reducing Escherichia coli contamination of household drinking water. Households were randomized to three study groups: two intervention groups that received either a safe storage container or a safe storage container plus water pasteurization indicator and a control group that continued usual practices. Although over 90% of households used an improved water source at baseline, 47% of source and 43% of stored water samples were contaminated with E. coli. Pouring or using a spigot to obtain water from the storage container instead of dipping a hand or object was associated with decreased risk of contamination of stored water (adjusted prevalence ratio (aPR)=0.58, 95% CI=0.42, 0.80). Container cleanliness (aPR=0.67, 95% CI= 0.45, 1.00) and correct handwashing technique (aPR=0.62, 95% CI=0.42, 0.90) were also associated with decreased contamination risk. During a 13-week follow-up period, households that received a safe storage container and water pasteurization indicator had a higher prevalence of stored drinking water contamination relative to the control group, although the difference was not statistically significant (Prevalence Ratio (PR): 1.20, 95% CI: 0.94, 1.52). Receipt of only a safe storage container had no effect on the contamination of stored drinking water (PR: 1.02, 95% CI: 0.79, 1.31). Although use of low-cost water pasteurization indicators and locally available storage containers did not significantly increase the safety of household drinking water in this study, future research could help illuminate factors that facilitate the use of these interventions to effectively improve water quality and reduce the risk of waterborne disease in populations that boil drinking water.