Aspects of intestinal parasitism in villagers from rural peninsular India

SUMMARYIn 1977, a parasitological survey was undertaken of stool samples collected from 335 people from 5 villages in semi-arid regions of peninsular India. Stools, which were collected from various individuals in a stratified sample of 40 matched households from each village, were examined by standard diagnostic procedures. Eggs ofAscaris lumbricoidesand protozoan cysts, which were identified on morphological grounds as belonging toEntamoebaspp., were most common. Other protozoan cysts were considered to be those ofBalantidium coli, and eggs of hookworm andHymenolepis nanawere also observed in some of the stool specimens. The prevalence of parasitic infections varied between villages. The village with the highest prevalence ofAscaris(70%) appeared to have the greatest demands made on its meagre drinking-water supply. This village is located in a dry, windy and dusty region and it is speculated that, in addition to well-established transmission mechanisms, the villagers may be exposed, perhaps through contamination of uncovered drinking-water wells and inhalation, to wind-borneAscariseggs. In 1967, a WHO Expert Committee Report on the Control of Ascariasis pointed out that information on the frequency of dust-borne infection withAscarisin man was inadequate.