SOIL-TRANSMITTED HELMINTHIASES - NATIONWIDE SURVEY IN CHINA

A total of 2848 study sites, with about 500 people in each, were rando mly sampled for this investigation which covered a total population of 1 477 742. By stool examinations using the Kato-Katz thick-smear and larval-culture techniques, overall prevalences of 47.0%, 18.8%, and 17 .2% were obtained for Ascaris lumbricoides, Trichuris trichiura, and h ookworm infections, respectively. The number of infections due to Asca ris, Trichuris, and hookworm was estimated as 531 million, 212 million , and 194 million, respectively. Egg counts showed that 75-95% of the subjects had light infections. Higher prevalences of ascariasis and tr ichuriasis were found in the age group of 5-9, 10-14 and 15-19 years, and among adults for hookworm. Students, farmers (including vegetable growers) and fishermen were the occupational groups with high infectio n rates. The prevalence of helminthiases was found to be closely assoc iated with climatic and geographical factors. In view of the morbidity and mortality due to these helminthiases, their control, particularly in shoolchildren, is very important.