Surveillance on schistosomiasis in five provinces of the People’s Republic of China in the post-elimination era

Abstract

Background: The People’s Republic of China (P. R. China) has made significant progress on schistosomiasis control. Among the 12 provinces (municipality, autonomous region) with schistosomiasis endemic in P.R. China, Guangdong, Shanghai, Fujian, Guangxi and Zhejiang provinces (following called as five provinces) had successively eliminated schistosomiasis during 1985-1995. However, given the increasing mobilization of the population and goods, wetland protection, climate changes etc., consolidation of the schistosomiasis elimination in these five provinces remains challenging. In the current study, we sought to understand the epidemic situation in these post-elimination areas and their surveillance capabilities on schistosomiasis. Methods: (Ⅰ) Through the national schistosomiasis reporting system, annual data reflecting the interventions and surveillance on human beings, cattle and snails based on county level from 2005 to 2016 were collected and analyzed to understand the epidemic status of schistosomiasis in five provinces. (Ⅱ) A standardized score sheet was designed to assess the surveillance capacity for schistosomiasis of selected disease control agencies in five provinces and ten counties. Assessment on surveillance capacity consisted of two parts: the first part focused on the capacity of testing skills including schistosomiasis diagnostic skills, identification of snails’ living and infection status; the second part was to assess the knowledge level about schistosomiasis and its control.Results: The comprehensive assessments showed that no local cases in humans and cattle or infected snail were found in these five provinces from 2005, and the surveillance abilities on schistosomiasis of the prevention and control institutions in five provinces were appropriate. However, from 2005 to 2016, a total of 221 imported cases were detected in Zhejiang, Shanghai and Fujian provinces, and 11.98 hm2 of new snail habitats were found in Zhejiang, Shanghai and Guangxi provinces. In addition, snail infestation reoccurred in 247.55 hm2 of former snail habitats since 2011.Conclusions: Elimination of schistosomiasis was consolidated successfully in five provinces of P.R. China due to effective and strong post-elimination surveillance. Comprehensive consolidation strategies should be focused on the elimination of residual snails and the prevention of imported infection sources among the five provinces to consolidate the achievements of schistosomiasis control.