Objective: A comparative study that aimed to investigate Echinococcus transmission dynamics was undertaken in 2000-03 and 2012 in a hyper-endemic community (Xiji County), Ningxia Hui Autonomous Region, China. Intermediate host populations (small mammal species for E. multilocularis; slaughtered livestock for E. granulosus) and humans (teenagers) were surveyed. Methods: Although human cases could not be determined by serology alone, seroprevalence was considered as indicating the level of human exposure to echinococcosis. Small mammals were trapped/index line transects were walked to detect small mammal indices, their trapping location geo-referenced and habitat characteristics recorded. Animals were dissected to identify potential lesions of larval Echinococcus sp. The inspection records of livestock diseases from the slaughter houses of Xiji County were searched in 2000-03. In 2012, due to economic policy shifts and the subsequent closure of the majority of the public slaughterhouses, the survey was undertaken in Xinglong, the largest outdoor livestock slaughter market () in Xiji. Results: Land cover has only marginally changed from 2003 to 2012; however some growth has been observed in reforested areas gradually shifting from set aside farmland to bushes. No small mammals were found infected during the survey. Our data indicate an important decrease of the populations of Spermophilus (ground squirrels) between 2003 and 2012; a large increase of Myospalax (Zokor) populations in reforested areas. Taking both trapping and transects results into account, they also show that Cricetulus longicaudatus (long-tailed dwarf hamster) represents 57-70% of the animals trapped in the small mammal community for the two periods considered. Overall the survey indicates the virtual absence of Arvicolid species in Xiji. The prevalence of E. granulosus in slaughtered sheep in Xiji appears to have decreased substantially from around 20% (n=877) based on scrutiny of abattoir records in 2000-03 to 0% (n=198) from personal attendance at Xinglong outdoor slaughter market in 2012 . However, there was increased sero-positivity to Echinococcus antigens in teenagers suggesting increased exposure to infection in this population (28% and 30%, n=59, 87 in Chengjiao and Haoziwan in 2000-03 compared to 50%, n = 200 in Chengjiao/county city in 2012). Conclusions: Our study confirms the dominance of Cricetine (hamsters) species on farmland in Xiji and the virtual absence of large Microtine species populations in the area. It indicates that land cover changes have led to a large increase of Myospalax populations in set-aside fields and shrubby habitats. It also demonstrates a substantial increase of anti-Echinoccocus antibodies in the teenage population. Paradoxically, an apparent decrease in sheep infection was observed. The discrepancy between the evolution of E. granulosus infections in livestock compared with echinococcosis in human teenagers raises the issue as to the nature of the driver(s) responsible for the increase of E. granulosus sero-prevalence in teenagers. Further studies are now necessary to answer this question.