Surveillance of schistosomiasis in Xiaogan City from 2016 to 2020 / 中国血吸虫病防治杂志

ABSTRACT

Objective To analyze the surveillance data of schistosomiasis in Xiaogan City, Hubei Province from 2016 to 2020, so as to provide the scientific evidence for understanding the epidemiological changes of schistosomiasis and evaluating the schistosomiasis control strategy. Methods A total of 16 surveillance sites were selected in the schistosomiasis endemic foci of Xiaogan City from 2016 to 2020, where Schistosoma japonicum infections in humans, livestock and Oncomelania snails and the schistosomiasis transmission risk were monitored. The schistosomiasis surveillance results were descriptively analyzed. Results During the period from 2016 to 2020, there was no schistosomiasis emergency epidemic in Xiaogan City. A total of 660 sero-positive individuals were identified in Xiaogan City during the 5-year period, and the seroprevalence of S. japonicum infections reduced from 2.08% in 2016 to 0.97% in 2020. Higher seroprevalence of S. japonicum infections was detected in men than in women, and in individuals at ages of over 60 years than in those at other age groups; however, no egg-positives were detected in humans or livestock. The mean density of living snails was 0.05 to 0.06 snails/0.1 m2 during the 5-year period, and the occurrence of frames with snails increased from 2.99% in 2016 to 3.92% in 2020; however, no S. japonicum infection was found in snails. Conclusions The endemic situation of schistosomiasis remarkably decreases in Xiaogan City during the period from 2016 through 2020. Further improvements of the sensitive and effective schistosomiasis surveillance system are required with an emphasis on the monitoring of the schistosomiasis transmission risk and management of floating populations.