Abstract:

Objective To understand case composition, regional distribution and lesion distribution of hydatid disease in Tibet Autonomous Region. Methods A stratified cluster sampling method was used to select 364 villages from 70 counties of 7 prefectures(cities) in Tibet Autonomous Region to perform an epidemiological survey on hydatid disease from August to October, 2016. B ultrasound was conducted on residents, accompanied by serological examination for suspected cases. Clinical and suspected cases were investigated individually. All the cases were finally identified by an imaging expert based on a combination of imaging and serological results. Negative cases were excluded. Data were analyzed by SPSS 20.0 software. Results A total of 77 049 residents received B ultrasound examination, and 1 230 were detected with hydatid disease(1.60%, 1 230/77 049), comprising 1 078 cystic echinococcosis (CE) (87.64%), 136 alveolar echinococcosis(AE) (11.06%), and 16 unclassified cases (1.30%). The 7 prefectures(cities) were all found with CE and AE cases, of which CE dominated the case composition with regard to city, gender, age, ethnicity, occupation, educational level, and type of production in place of residence. The cases were dominated by those uneducated 71.95% (875/1 214). There was a significant CE case accumulation with the increase of age. Among different occupations, the CE case composition of herdsmen (91.02%) was higher than that of farmer-and-herdsmen (87.78%) (χ² = 10.710, P < 0.05). Lesions distributed mainly in the right liver, with > 79% cases having only one focal lesion. Conclusion There is a wide prevalence of hydatid disease in Tibet Autonomous Region, and herdsmen are the major target population for control.

Key words: Tibet Region, Cystic echinococcosis, Alveolar echinococcosis, Case analysis