Wednesday, 30 June 2010

Water, sanitation, women and children

Here’s an interesting World Bank Policy Research Working Paper: Access to Water, Women’s Work and Child Outcomes, by Gayatri Koolwal and Dominique van de Walle (both of the World Bank), published in May this year. This is the Abstract:

Poor rural women in the developing world spend considerable time collecting water. How then do they respond to improved access to water infrastructure? Does it increase their participation in income-earning market-based activities? Does it improve the health and education outcomes of their children? To help address these questions, a new approach for dealing with the endogeneity of infrastructure placement in cross-sectional surveys is proposed and implemented using data for nine developing countries. The paper does not find that access to water comes with greater off-farm work for women, although in countries where substantial gender gaps in schooling exist, both boys’ and girls’ enrolments improve with better access to water. There are also some signs of impacts on child health as measured by anthropometric z-scores.

Anthropometric z-scores? See here.

Could the same approach be taken for rural sanitation? I don’t see why not.

There’s another very pertinent World Bank Policy Research Working Paper: Water, Sanitation and Children’s Health Evidence from 172 DHS Surveys, by Isabel Günther of ETH Zürich and Günther Fink of the Harvard School of Public Health, published in April. Here’s the Abstract:

This paper combines 172 Demography and Health Survey data sets from 70 countries to estimate the effect of water and sanitation on child mortality and morbidity. The results show a robust association between access to water and sanitation technologies and both child morbidity and child mortality. The point estimates imply, depending on the technology level and the sub-region chosen, that water and sanitation infrastructure lowers the odds of children to suffering from diarrhea by 7–17 percent, and reduces the mortality risk for children under the age of five by about 5-20 percent. The effects seem largest for modern sanitation technologies and least significant for basic water supply. The authors also find evidence for the Mills-Reincke Multiplier for both water and sanitation access as well as positive health externalities for sanitation investments. The overall magnitude of the estimated effects appears smaller than coefficients reported in meta-studies based on randomized field trials, suggesting limits to the scalability and sustainability of the health benefits associated with water and sanitation interventions.

Mills-Reincke Multiplier? The following explanation comes from the 1910 paper On the Mills-Reincke phenomenon and Hazen's theorem concerning the decrease in mortality from diseases other than typhoid fever following the purification of public water supplies by W. T. Sedgwick and J. S. MacNutt, published in the Journal of Infectious Diseases (volume 7, issue 4, pages 489–564):

It is nowadays commonly understood that the purification of a polluted water-supply produces a marked decrease in the mortality from typhoid fever among persons using the water for drinking and other domestic purposes, but it is not as yet generally recognized that such purification produces also a marked decrease in deaths from other diseases. In 1893−94 it was observed, independently, by Messrs. Hiram F. Mills, C.E., of Lawrence, Massachusetts, and Dr. J. J. Reincke, of Hamburg, Germany, that the purification of the polluted public water-supplies of Lawrence and of Hamburg, respectively, was producing a notable decline in the general death-rate of each of these cities. The attention of Mr. Allen Hazen was about the same time turned to the subject, and some years later, in a paper presented to the International Engineering Congress held at the St. Louis Exposition in 1904, he drew from an examination of the death-rates of certain cities which had radically improved polluted water-supplies the following conclusion:

Where one death from typhoid fever has been avoided by the use of better water, a certain number of deaths, probably two or three, from other causes have been avoided.

This novel statement has not hitherto received the attention which it deserves …