Survey on cystic echinococcosis in Tibetans, West China.

Human cystic echinococcosis (CE) is a serious public health problem in West China. The Tibetan has a nature relation with these definitive and intermediate hosts in West China. Although Tibet is CE endemic, a few community studies have been reported. Eight hundred and eighty two Tibetans residing in the three rural communes of Tianzhu County, Gansu province of West China were investigated by serology and ultrasound scanning. 11.2% serum antibody positive rate in ELISA test was found out, and a 12.1% ultrasound rate of hepatic CE was found in the sero-positive population. Seropositivity rates varied for communes between 7.6 and 13.7%. Overall, females had a significantly greater risk of infection than males-ratio was about 2:1. The local behaviors were investigated and showed that family dog and grazing could not effect the infectious rates, but the number of sheep owned a family had a positive correlation with the infection rates. The infectious rate of hunting population was significantly higher than that of no-hunting population. The educated level of Tibetans in school had no effect on the infected rates.