Water, Sanitation, and Hygiene
Water and sanitation problems are a major source of health problems in the developing world. Projects that aim to build better infrastructure are typically not as cost-effective as many other forms of health intervention. However, projects aiming to educate people about the problem and promote more hygienic forms of behaviour can be much more cost-effective.
Water, Sanitation, and Hygiene programs (commonly referred to as ‘WASH’) come in two broad classes.
Construction Programs
Construction programs involve the construction of infrastructure that improves water supply, such as boreholes, stand posts and dug wells, or infrastructure that improves sanitary conditions, such as sewerage, septic tanks and latrines. According to the report by the Disease Control Priorities Project (DCP2), the construction programs are surprisingly ineffective relative to their cost:1
“Providing a public water point appears to have little effect on health, even where the water provided is of good quality and replaces a traditional source that was heavily contaminated with fecal material.”
Reference:
| 1. | Disease Control Priorities In Developing Countries (DCP2), Chapter 41, p. 777. (Close footnote) |
Their cost-effectiveness has been estimated as less than a tenth that of some other ways of promoting health. Using the measurement of Disability Adjusted Life Years (DALYs), the cost-effectiveness ranges from 3.7 DALYs / $1000 (for a combined program of sanitation construction and promotion) to 10.5 DALYs per $1000 (for the construction of a hand pump or stand post).2
Reference:
| 2. | Disease Control Priorities Project, table of interventions. (Close footnote) |
Promotion Programs
Promotion programs attempt to change behaviour regarding sanitation and hygiene, for example via education about the importance of handwashing and the provision free soap. Our evidence currently suggests that sanitation promotion and hygiene promotion are highly cost-effective. The DCP2 report states that sanitation promotion has a cost-effectiveness of 90 DALYs per $1000. 3 This is similar to the cost-effectiveness of providing insecticide treated bednets, a highly cost-effective intervention.
Reference:
| 3. | See Table 41.12 in the DCP2 report. (Close footnote) |
Hygiene promotion appears to be even more effective. Though the DCP2 report notes that there is regrettably little evidence concerning its cost-effectiveness, it estimates that the hygiene promotion has a cost-effectiveness of 300 DALYs per $1000.4 If this figure is correct, hygiene promotion is extremely cost-effective, similar to the cost-effectiveness of treating some neglected tropical diseases. Moreover, it's possible that this figure is an underestimate, because DCP2 only assesses the impact on diarrheal disease, even though hygiene promotion also helps to prevent other diseases as well.
Reference:
| 4. | Disease Control Priorities Project, table of interventions. (Close footnote) |
GiveWell (an organisation dedicated to analysing charity cost-effectiveness) is more sceptical of water charities.5 However, they only consider the construction aspect of WASH, and neglect the promotion aspect, so this scepticism may be unwarranted.
Reference:
| 5. | See the GiveWell report on ‘Water supply programs to prevent disease’. (Close footnote) |
Because sanitation and hygiene promotion, look so promising as intervention types, we are currently undertaking further research into this area, which will be published on this web page as soon as it is completed.
