Assessment of Clonorchis Sinensis Epidemic Trends and Its Natural Epidemic Focus in Northern Area of Zhejiang Province

Objective To understand the Clonorchis sinensis epidemic trends and its infection status in intermediate host.MethodsThe varied freshwater fish and shrimp were collected to detect the Clonorchis sinensis infection rate in second intermediate hosts.The venous blood samples from target populations were collected and the serum was separated for the detection of Clonorchis sinensis antibody by ELISA.Results The infection rate in second intermediate hosts was 24.86%(135/543).There were statistically significant differences of the detected rates in different kinds of fish(P0.01),among which the highest infection rate was 35.53% in Abbottina rivularis,followed by 19.29% in Pseudorasbora parva.The positive rate of metacercaria was higher in high river network rate than in low one(30.32% vs 8.21%,P0.01).The general antibody positive rate was 2.31% in human.Conclusion There was high infection rate(24.86%) of metacercaria of Clonorchis sinensis in second intermediate hosts in northern Zhejiang area.It indicated that there might be some epidemic focus in these areas.