Effect of intensive handwashing promotion on childhood diarrhea in high-risk communities in Pakistan : a randomized controlled trial

This study evaluates the effect of promoting household handwashing with soap among children, especially those younger than 1 year, who are at the highest risk of death from diarrhea. A cluster randomized controlled trial was carried out among 36 low-income neighborhoods in urban squatter settlements in Karachi, Pakistan. Field workers visited participating households at least weekly from April 15, 2002, to April 5, 2003. Eligible households located in the study area had at least 2 children younger than 15 years, at least 1 of whom was younger than 5 years. Weekly visits were carried out in 25 neighborhoods to promote handwashing with soap after defecation and before preparing food, eating, and feeding a child. Within intervention neighborhoods, 300 households (1523 children) received a regular supply of antibacterial soap and 300 households (1640 children) received plain soap. Eleven neighborhoods (306 households and 1528 children) comprised the control group. The study found that children younger than 15 years living in households that received handwashing promotion and plain soap had a 53% lower incidence of diarrhea (95% confidence interval [CI], -65% to -41%) compared with children living in control neighborhoods. Infants living in households that received handwashing promotion and plain soap had 39% fewer days with diarrhea (95% CI, -61% to -16%) vs infants living in control neighborhoods. Severely malnourished children (weight for age z score,