Interventions to improve sanitation for preventing diarrhoea

What is the aim of this review?

The aim of this Cochrane Review was to assess if diarrhoea is reduced by sanitation interventions to provide, upgrade, or encourage people to use toilets or latrines. We collected and analysed all relevant studies of certain prespecified rigorous study design types and found 51 studies involving 238,535 people.

Key messages

We found evidence that sanitation interventions may be protective against diarrhoea. However, the effects varied by the type of intervention and setting, and the certainty of the evidence ranged from very low to moderate. 

What was studied in this review?

Diarrhoea is a major cause of death and disease, especially amongst young children in low‐income countries. Many of the pathogens that cause diarrhoea are transmitted through exposure to human faeces. Sanitation facilities, such as toilets and latrines, serve as a primary barrier to separate pathogens excreted in human faeces from the environment. This review examined intervention studies to improve sanitation access, facilities, or use. We identified 51 studies of such interventions, most of which were from low‐ or middle‐income countries.

What were the main results of this review?

The results suggest that sanitation interventions reduce diarrhoea by about 15% to 26%, both in vulnerable young children and all age populations. However, not all interventions were protective, and effects varied substantially by the type of intervention and setting. We estimated that an intervention to provide sanitation access to people practising open defecation would probably reduce diarrhoea by about 11% to 21%, an intervention to improve existing sanitation facilities may reduce diarrhoea by about 15% to 35%, and a behaviour change intervention to improve sanitation access or use without providing infrastructure or subsidies would probably reduce diarrhoea by about 15% to 18%. However, the certainty of the evidence ranged from moderate to very low, and additional research is likely to change these estimates, particularly for interventions that provide sanitation access or improve existing sanitation facilities. Further research is also necessary to understand which type of interventions would yield the most protective health effects in various types of settings.

How up‐to‐date is this review?

We searched for studies that had been published up to 16 February 2022.