ABSTRACT
Objective To explore the risk factors of newly emerging advanced schistosomiasis patients in endemic areas.Methods The study areas were selected in two counties of Dongting Lake regions and a 1 :2 match case-control study was designed.Sixty schistosomiasis patients,who newly evolved into advanced schistosomiasis from 2006 to 2007,were selected into the case group,and 120 cases with chronic schistosomiasis into the control group.Questionnaires including potential risk factors of advanced schistosomiasis were designed and the information was collected based on face to face interviews.SPSS 12.0 was used to analyze the simple factors and multi ones (logistic regression) attributable to the development of advanced schistosomiasis.Results The history of hepatitis B (OR = 10.729),models of water contact (OR = 3.919) ,yearly exposure days to the infested water (OR = 5.457) and times of chemotherapy in the nearly 10 years(OR = 1.578) were the risk factors of development of advanced schistosomiasis.The times of examinations with positive schistosome eggs were protective factors.No association was found between yearly income,education degree,times of checking for schistosomiasis,times of examination with sera positive results and the emergence of advanced schistosomiasis.Conclusion The high frequency of exposure to the infested water,repeated infections,incomplete diagnosis and treatment are the risk factors of advanced schistosomiasis.The concurrent infection with hepatitis B is associated with the acceleration of development of advanced schistosomiasis.