Prevalence of intestinal parasites in rural Southern Indians

OBJECTIVE To determine the prevalence of intestinal protozoal and helminthic infection in a rural population. METHOD Seventy-eight members of 15 families from a village were studied. Stool samples from all subjects were examined on alternate days for one month. RESULTS The overall prevalence rate of various parasitic infections was 97.4%, with only 2 of 78 subjects not excreting parasites in any of their 15 samples. Eighteen (23.1%) persons had only one type of parasite, while 58 (74.3%) excreted multiple parasites. Giardia and Cryptosporidium were the commonest protozoan infections, affecting 42/78 (53.8%) and 31/78 (39.7%), respectively. Hookworm infestations were the commonest helminthic infections, seen in 48/78 (61.5%). Based on excretion patterns, the asymptomatic individuals could be divided into 2 groups of infrequent and frequent excretors, indicating that the host response may determine the level of parasite replication in the gut.