Rice, a challenge to health.

Irrigation can bring enormous rewards to a hungry world. For example by allowing agriculture in arid and semi-arid areas, by extending the growing season, and by giving higher crop yields. The most extensively irrigated crop is rice. This is where problems arise, because as rice fields are usually flooded for long periods, they provide ideal breeding places for mosquito vectors. Here Mike Service discusses some o f the health hazards, in particular malaria, that are often associated with rice cultivation, and the environmental measures that are sometimes employed to combat these problems.