Abstract:

Objective To understand the prevalence and distribution of echinococcosis in Wenquan County of Xinjiang, and provide evidence for control of this disease. Methods In 2009-2014, B ultrasound scan of the abdomen was conducted to examine hydatid cyst infection in populations randomly selected in 74 villages in Wenquan County. ELISA was performed to detect serum IgG antibody against hydatid cyst in 6-12-year-old students. Visceral necropsy was performed to examine hydatid cyst infection in livestocks at slaughter house. Dog feces were collected, and hydatid cyst antigen was examined by ELISA. Results A total of 49 627 people were examined, with an average age of 36 years （5-89 years）. Among them, 192 （0.39%） were determined to be positive for cystic echinococcosis. The morbidity showed a trend of decrease during 2009-2014, highest in 2009（1.22%, 72/5 919） and lowest in 2014 （0.17%, 15/9 011）. There was no significant difference in morbidity between males （0.34%, 72/21 226） and females（0.42%, 120/28 401）. The disease was mainly distributed in age range of 20-59 years （91.67%, 176/192）. There was no significant difference on morbidity in agricultural areas（0.43%, 130/30 492）, pastoral areas （0.33%, 49/14 649） and towns （0.29%, 13/4 486）. The morbidity in herdsmen （0.34%, 86/24 963） was significantly higher than that in those with other occupations. The morbidity was higher in Mongolian（0.51%, 45/8 696） and Kazak （0.42%, 49/11 434） than that in other ethnic groups, and highest in the illiterates （1.92%, 63/3 285）. ELISA showed that the positive rate for serum antibody against hydatid cyst was 3.60% （265/7 369） in 7 369 students examined, and showed a trend of decrease from 2009 （6.06%, 37/611） to 2014（2.59%, 22/850）; the positive rate was higher in agricultural areas （3.99%, 207/5 193） than that in pastoral areas （2.89%, 3/1 487） and towns （2.18%, 15/689）（P<0.05）, and highest in Han students （4.06%, 177/4 361）. The hydatid cyst infection rate in 4 677 livestocks was 13.04% （610/4 677）, decreased from 25.05% （127/507） in 2009 to 8.80% （44/500） in 2014. The positive rate of hydatid cyst antigen in dog feces was 5.18% （365/7 049）, decreased from 16.98% （81/477） in 2009 to 2.56% （41/1 600） in 2014. Conclusion The morbidity of echinococcosis showed a trend of decrease in Wenquan County, and most of the patients are young adults. There remains a high level of echinococcosis morbidity, positive rate of serum echinococcosis antibody in 6-12-year-old students, infection rate in livestocks, and existence of hydatid cyst antigen in dog feces.

Key words: Echinococcosis, Epidemiology, Investigation, Wenquan County, Xinjiang