Handwashing with soap prevents diarrhoea, pneumonia, and impetigo in squatter communities in Pakistan

Families in Pakistan can dramatically reduce their children's risk of diarrhoea or pneumonia simply by washing their hands more often with soap. In a randomised trial in Karachi, weekly encouragement of handwashing and bathing and a free supply of soap reduced the incidence of pneumonia in children aged < 5 years by 50% (2.2 v 4.4 cases/100 person weeks) and the incidence of diarrhoea in children aged < 15 by 53% (1.9 v 4.06). Bathing with soap also reduced the incidence of impetigo by a third compared with the incidence in control neighbourhoods, where researchers visited households but did not discuss hygiene.

Researchers randomised 36 poor neighbourhoods in Karachi, including 906 households with a mean of nearly 10 residents each. The intervention was fairly intensive, with field workers holding community meetings, showing videos, and visiting households once a week for a year. The hard work and free soap (from the sponsors Procter and Gamble) paid off, but the authors think their intervention may be too expensive to roll out to all poor communities in the developing world. They have shown once again that handwashing protects against common and lethal infectious diseases. The challenge now is to find a cheap way to promote it.

Lancet 2005;366: 225-33

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