[Epidemiological studies on Clonorchis sinensis infection along the Zhujiang River in Lou village of Shenzhen].

OBJECTIVE

To study the transmission route and epidemiological features of Clonorchis sinensis infection in Shenzhen area--the biggest immigration city of Southern China.

METHODS

In this study, we examined 1473 individuals (710 males and 763 females) to determine the current status of C. sinensis infection among the people in one village in Zhujiang river region, Guangdong province, China. Blood samples were detected on antibody of C. sinensis with enzyme linked immunosorbent assay,and stool specimens from sera positive cases were examined by modified Kato-Katz thick smear to confirm the density of infection. People were interviewed on their life styles under the structured questionnaire which was administered by trained staff members. Major content of the questionnaire included eating raw fish, using the same utensils for both raw fish and cooked food, using feces of domestic animals and human feces to feed fish and so on.

RESULTS

Among 1473 people examined, 70 (4.75%) were found infected with C. sinensis. By counting eggs per gram feces (EPG), it was found that heavy intensities of infection in males was stronger than that of females,and the overall average EPG was 41.87. Of 1473 interviewees, 54% of them did not know about fluke disease or its transmission route, 12% of those who knew about the fluke but believed that the infection caused no harm or only slight harm to their health. 27% of the interviewees ate raw fish at least 1-2 times per months with 5% of the families using the same utensils for both raw fish and cooked food. 40% of the fish ponds owners fed their fish with the feces of domestic animals and human feces.

CONCLUSION

Together with these results, unhealthy behaviors, poor knowledge, inappropriate farming/fishery practices, eating raw fish were important factors influencing the C. sinensis prevalence in humans.