The effects of management of infection source of echinococcosis in Linzhi, Tibet autonomous region of China

Abstract Background Echinococcosis is highly endemic in western and northern China, Tibet Autonomous Region （TAR）is one of the most serious prevalent areas where the prevalence of echinococcosis in 2016 was 1.66% in humans and dog infection rate was 7.30%. Linzhi is located in southeastern part of TAR where the prevalence of echinococcosis in 2016 was 1.55% in humans and in dog infection rate was 7.28%.Dogs are the main infection source for the transmission of echinococcosis to humans. A control and prevention campaignbased on dog management has been conductedin the past three years. This study is toevaluate the effects of dog management on infection rate of dogs.Methods Data of dog population, registration and de-worming of 7 counties/district in Linzhi from 2017 to 2019 were collected. Domestic dog fecal samples were collected from each endemic town of7 counties/district in Linzhiin 2019 to determine the infection of dogsusing coproantigen ELISA. Data analysis was processed using SPSS statistics to compare dog infection rate between 2016 and 2019 by chi-square test, and maps were mapped using ArcGIS.Results In Linzhi, domestic dog population decreased from 17407 in 2017, 16512 in 2018, to 12663 in 2019, whilethe registration rate increased from 75.92% in 2017, 95.48% in 2018, to 98.64% in 2019. Similarly, stray dog populationdecreased from 14336 in 2017, 13067 in 2018, to 11837 in 2019, while sheltered rateincreased from 84.63% in 2017, 92.32% in 2018, to 96.63% in 2019.Dog de-worming frequency increased from 4 times per annum in 2017 to 12 times in 2019, indicating almost every dog was dewormed monthly. A total of 2715 dog fecal samples were collected for coproantigen ELISA assay. The dog infection rate was 2.84% (77/2715) in 2019, which was significantly lower than7.28% (45/618) in 2016 (P＜0.05).Conclusion Increased dog registration, decreased dog population and increased dog de-worming frequency contributed to significantly decreased dog infection rate in Linzhi, TAR. Control and prevention campaign based on dog management can significantly decrease dog infection with Echinococcus spp in echinococcosis endemic areas.