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Re-emergence of schistosomiasis in regions of China where control programs have ceased requires development of molecular-genetic tools to track gene flow and assess genetic diversity of Schistosoma populations. We identified many microsatellite loci in the draft genome of Schistosoma japonicum using defined search criteria and selected a subset for further analysis. From an initial panel of 50 loci, 20 new microsatellites were selected for eventual optimization and application to a panel of worms from endemic areas. All but one of the selected microsatellites contain simple tri-nucleotide repeats. Moderate to high levels of polymorphism were detected. Numbers of alleles ranged from 6 to 14 and observed heterozygosity was always >0.6. The loci reported here will facilitate high resolution population-genetic studies on schistosomes in re-emergent foci. [ABSTRACT FROM AUTHOR]

Background to the debate: Triggered by a fascinating publication in the New England Journal of Medicine detailing China's new multi-pronged strategy to control and eventually interrupt the transmission of Schistosoma japonicum, this PLoS Neglected Tropical Diseases Debate critically examines the generalizability and financial costs of the studies presented from the marshlands of the lake region. Edmund Seto from the University of California and colleagues emphasize that the epidemiology and control of schistosomiasis varies according to the social-ecological context. They conjecture that the successful intervention packages piloted in the lake region is not fully fit for the hilly and mountainous environments in Sichuan and Yunnan provinces, and hence call for more flexible, setting-specific, and less expensive control strategies. In response, Xiao-Nong Zhou from the National Institute of Parasitic Diseases at the Chinese Center of Disease Control and Prevention and colleagues explain the steps from designing pilot studies to the articulation and implementation of a new national control strategy through a careful process of scaling-up and adaptations. Finally, the two opponents converge. The need for integrated, intersectoral, and setting-specific control measures is stressed, supported by rigorous surveillance and continuous research. Experiences and lessons from China are important for shaping the schistosomiasis elimination agenda. [ABSTRACT FROM AUTHOR]

The article presents a debate regarding sustainable and comprehensive control of schistosomiasis in China. It offers the perspective of various authors including Edmund Seto, Justin Remais and Elizabeth Carlton regarding the effort of the country to reduce the prevalence of Schistosoma japonicum through a strategy based on chemotherapy and snail control. It discusses the difficulty of the country to eliminate the prevalence of the disease due to the high rates of reinfection. It also provides a response by various authors including Li-Ying Wang, Yang Hao, and Robert Bergquist regarding the issue on sustainable implementation of the control strategy in the Chinese national schistosomiasis control program.