Agro-engineering and sanitation improvement in the control of schistosomiasis japonica in the Philippines: a review.

Measures that would change the habitat of the snails were found to prevent its breeding. Among these are clearing and drainage of waterlogged areas; filling of depressions where filling materials are available; ponding of areas which cannot be drained, and improved rice culture. The degree of success in snail control depends to a large extent on the amount of change brought about in the habitat. The more radical the change, the greater the reduction in snail density. It can be expected that improvement in sanitation in the form of toilet construction and use, provision of safe water supply, building of footbridges and the control of stray animals will bring a further decline in the transmission of the disease. Studies have shown that perfect sanitation in the form of toilet construction and use will reduce transmission by about 75%, the other 25% being contributed by lower mammals. Agro-engineering control measures are presently being carried out intensively in 7 town of Leyte, with food assistance from the UN/FAO World Food Program being given to volunteer workers as incentives for them to work. Snail evaluation after 2 years has shown a snail reduction by 72% in the areas covered. It may be mentioned here that sanitation improvement, especially latrine construction, is an ongoing program of the Department of Health in all rural areas.