Abstract: Objective  To analyze the epidemiological status of echinococcosis among children in three different zones of Qinghai Province.  Methods   B-ultrasound and ELISA were used in the survey to evaluate echinococcus infection among 6～15 year old children in the three zones，namely，Qinghai southern plateau，Qilian mountain-Hehuang valley and Chaidamu basin.   Results  The prevalence of echinococcus infection scanned by B-ultrasound and sera positive rate detected by ELISA in children were 1.5%(320/20 730)and 6.5%(1024/15 762）respectively，and the prevalence of cystic echinococcosis and alveolar echinococcosis by ultrasound were 1.0%（206/20 730）and 0.6%（114/20 730），respectively. The prevalence and sera positive rate were 9.5%（707/7 453)and 2.3%（269/11 618） in Qinghai southern plateau, 3.8%（289/7 544) and 0.6%（50/8 275) in Qilian mountain-Hehuang valley, and 3.7%（28/765)and 0.1%（1/837) in Chaidamu basin, respectively. The southern plateau showed the highest prevalence, with a significant statistical difference among the three areas(P<0.01). The prevalence of alveolar echinococcosis was 1.0%(114/11 618)in the southern plateau, but no alveolar echinococcosis patients were found in other two areas. Correlation analysis showed that the prevalence increased with the altitude (r _s-e=0.96，P<0.05，R ²=0.93；r _p-e=0.82，P<0.05，R ²=0.67).  Conclusion  The prevalence of echinococcosis among children shows an apparent geographical difference in Qinghai Province.

Key words: Qinghai Province, Children, Echinococcosis, Geographical Distribution