Epidemiological studies on guinea-worm infection.

Dracontiasis is one of the most easily preventable of the tropical parasitic diseases, yet in India the infection is still present in large numbers of people and causes extreme degrees of morbidity and incapacitation.The 10 000 inhabitants of 4 villages in South India were interviewed and the prevalence of guinea-worm infection was found to vary from 11% to 54%; the prevalence increased with the proportion of the population using step-wells. Questioning revealed that infections with more than one worm at a time had occurred in 707 out of 1759 infected persons, that reinfections were common and that many people had suffered for long periods.A survey of the water supplies in a district of South India with a population of about 1.87 million showed that more than 0.5 million people were at risk of contracting the disease. The necessity for protected water supplies and for the conversion of step-wells into draw-wells is urgent.