Interventions to improve disposal of human excreta for preventing diarrhoea

Diarrhoea is a major cause of death and disease, especially among young children in low-income countries. Many of the microbial agents associated with diarrhoea are transmitted via the faecal-oral route and are associated with exposure to human faeces. This review examined trials of interventions to improve the safe disposal of human faeces to prevent diarrhoea. In low-income settings, among the estimated 2.6 billion people who lack basic sanitation, this mainly consists of introducing or expanding the number and use of latrines and other facilities to contain or dispose of faeces. We identified 13 studies of such interventions involving more than 33,400 people in six countries. These trials provide some evidence that excreta disposal interventions are effective in preventing diarrhoeal diseases. However, major differences among the studies, including the conditions in which they were conducted and the types of interventions deployed, as well as methodological deficiencies in the studies themselves, makes it impossible to estimate with precision the protective effective of sanitation against diarrhoea. Further research, including randomized controlled trials, is necessary to understand the full impact of these interventions.