[Evolution of schistosomiasis epidemics in China during the past seventy-five years: reconstruction and implications...

To systematically reconstruct the evolution of schistosomiasis prevalence in China from 1950 to 2024, so as to fill the gap of national data on schistosomiasis prevalence in China before 1986.

Schistosomiasis control data were collected from schistosomiasis-endemic areas of China before 1986, which mainly included statistical data on schistosomiasis, compilations of control records, annual work reports, and academic papers. Data pertaining to the prevalence of schistosomiasis from each province (autonomous region, municipality) were collected and summarized annually, and integrated into national annual work reports for schistosomiasis control in China from 1986 to 2024 to build a national schistosomiasis epidemic database covering schistosomiasis patients, cattle with schistosomiasis, and Oncomelania hupensis snails. The provincial-level epidemic data of schistosomiasis were summarized annually from 1986 to 2024 with pivot tables, and then the national epidemic data of schis tosomiasis were summarized. The temporal trends in key epidemic indicators of schistosomiasis were analyzed in China from 1950 to 2024.

A complete time-series dataset of schistosomiasis was established in China from 1950 to 2024 through systematic reconstruction of multi-source historical documents and materials. A total of 1.97 million newly detected schistosomiasis cases were recorded in China from 1950 to 2024, and the actual number of schistosomiasis patients was all more than 1 million each year from 1955 to 1978. There were only more than 20 000 advanced schistosomiasis patients in China by the end of 2024, and the prevalence of Schistosoma japonicum human infections reduced from 34.6% in 1950 to below 1.0% after 1996. A total of 2.47 million cattle were tested positive for schistosomiasis, and the prevalence of S. japonicum infections reduced from 21.4% in bovines since 1950. The area of emerging O. hupensis snail habitats was concentrated during the period between 1956 and 1958, accounting for 49.8% of total areas, while the area of emerging O. hupensis snail habitats significantly decreased since 1992, indicating a stable distribution pattern of O. hupensis snails. Data validation results showed that the cumulative variation in areas of O. hupensis snail habitats was 1.6%, and the cumulative variation in the number of schistosomiasis cases was 1.4%. Join-point regression analysis revealed four turning points in the prevalence of S. japonicum infections in humans and seven turning points in the prevalence of S. japonicum infections in livestock across China from 1955 to 2024.

Through the joint efforts of the Communist Party of China and government leadership, interdepartmental collaboration, professional teams, scientific and technological innovation, and public participation, the schistosomiasis epidemic has been effectively controlled in China following active control for more than 70 years. This study builds, for the first time, a complete time-series dataset on schistosomiasis in China, which provides insights into assessment of the effectiveness of schistosomiasis control programmes and refinement of the experience from schistosomiasis control programmes in China.