Parasitic Diseases: Snail's Plague

The disease is as old as the pharaohs -telltale traces remain in mummies 3,000 years old—but to the dismay of public health doctors, it is more prevalent than ever. Schistosomiasis, bilharziasis, snail fever—by whatever name, the debilitating and often fatal illness afflicts more than 150 million people in Africa, Latin America and Asia. The disease is almost unknown in the U.S.; the few scattered cases brought into the country each year by visitors and immigrants fail to spread, create no public problem.

Cause of all the trouble is a wiggly tailed, microscopic larva...