Objective To evaluate the role of new strategy in the transmission control of schistosomiasis in Poyang Lake re-gion. Methods The information and epidemic data of schistosomiasis control were collected and analyzed in Poyang Lake re-gion from 2005 to 2016. Results After eleven years of carrying out the new strategy,thirteen counties achieved the objective of transmission control in Poyang Lake region. In 2016,the number of schistosomiasis cases and human infection rate were 10301 and 0.03％,decreased by 89.64％and 99.45％compared with those in 2005,respectively. The number of cattle and schistosome-infected cattle were 68152 and 5,decreased by 50.84％and 99.83％compared with those in 2005,respectively. The average density of Oncomelania hupensis snails was decreased by 61.52％. No schistosome-infected snails were found since 2014. Con-clusion The new strategy accurately locates the key points and targets of schistosomiasis transmission chain ,which has con-trolled the human and animal's fecal eggs from polluting grassland,and cut off the transmission chain,reduced both the infec-tion rates of human and animal and the re-infection risk,and promoted to achieve the target of schistosomiasis transmission con-trol in Poyang Lake region.

Objective To investigate the effectiveness and cost of 50% and 80% wettable powder of niclosamide ethanolamine salt (NESWP) and 26% metaldehyde and niclosamide suspension concentrate (MNSC) in hilly schistosomiasis-endemic regions, so as to provide insights into the selection of chemical molluscicides in hilly regions. Methods In September 2020, a wasteland in Guanshanqiao Village, Yanrui Township, Yushan County of Jiangxi Province was selected as the experimental region, which was sectioned into five blocks and defined as four experimental groups (A₁, A₂, B, C) and a blank control group (D). 80% NESWP were given at doses of 1 g/m² and 1.5 g/m² in groups A₁ and A₂ using the spraying method, 50% NESWP was given at a dose of 2 g/m² in Group B using the spraying method, and 26% MNSC was at a dose of 4 g/m² in Group C using the spraying method, while no chemical treatment was given in Group D. Snail survey was performed using a systematic sampling method before chemical treatment and 1, 3, 7 d and 15 d post-treatment to examine the molluscicidal effect, and all molluscicidal costs were estimated to calculate the cost of chemical treatment per 1 m² and the cost of the reduction in the mean density of living snails per 1%. Results The highest mortality of snails was 78.95% and the lowest density of living snails was 0.2388 snails/0.1 m² in the experimental groups within 7 d of chemical treatment, and the highest mortality of snails was 94.74% and the lowest density of living snails was 0.058 0 snails/0.1 m² 7 d post-treatment. There were no significant differences in the snail mortality among the A₁, A₂, B and C groups 1 (χ² = 2.250, P > 0.05), 3 (χ² = 1.779, P > 0.05) or 15 d post-treatment (χ² = 2.286, P > 0.05), while a significant difference was detected in the snail mortality among the four groups 7 d post-treatment (χ² = 7.990, P = 0.046). In addition, there were no significant differences in the snail mortality between A₁ and A₂ groups 1 (χ² = 0.724, P > 0.05), 3 (χ² = 0.584, P > 0.05), 7 (χ² = 0.400, P > 0.05) or 15 d post-treatment (χ² = 0.251, P > 0.05). The costs of chemical treatment per 1 m² were 0.58, 0.60, 0.64 Yuan and 0.73 Yuan in groups A₁, A₂, B and C, and the costs of the mean density of living snail per 1% reduction were 19.29, 20.44, 21.68 Yuan and 23.53 Yuan in groups A₁, A₂, B and C, respectively. Conclusion 80% NESWP shows a high molluscicidal efficacy and low cost in hilly schistosomiasis-endemic regions.

Objective To understand the situation of Schistosoma japonicum infections in wild animals in transmission-controlled schistosomiasis-endemic areas in Jiangxi Province, so as to provide scientific evidence for implementing precision control interventions and achieving the goal of transmission interruption and elimination of schistosomiasis. Methods Five endemic villages from Ruichang City and Pengze County that were heavily endemic for schistosomiasis in Jiangxi Province, were selected as the study villages. Wild animals like wild mice were captured, and the livers of wild animals were purchased from the snail habitats in the study villages for detection of S. japonicum infections. In the study villages, S. japonicum human infections were screened using indirect hemagglutination assay (IHA) followed by parasitological examinations with miracidial hatching test and Kato-Katz method, and the S. japonicum infection in livestock was tested using a miracidial hatching test with a plastic tube. In addition, snail survey was conducted in the study villages by means of systematic sampling combined with environmental sampling, and the S. japonicum infection in snails was detected using a loop-mediated isothermal amplification (LAMP) assay. Results A total of 240 liver specimens were sampled or purchased from 5 species of wild animals in the study villages, including wild mice, weasels, pigs, deer and rabbits. A total of 172 wild mice were captured, with a 2.91% rate of S. japonicum infection, and there was no S. japonicum infection detected in other wild animals. The prevalence of Capillaria hepatica infection was 12.21%, 1.96% and 12.50% in wild mice, deer and pigs, respectively. In addition, there was no S. japonicum infection found in either humans or livestock in the study villages, and the mean snail density varied from 0.13 to 0.80 snails/0.1 m² in the study villages. LAMP assay detected S. japonicum infection in 2 tubes in a study village. Conclusions The role of wild animals in schistosomiasis transmission and their potential risks can not be neglected in hilly schistosomiasis-endemic areas of Jiangsu Province after transmission control. Intensified surveillance and targeted control measures should be implemented to consolidate schistosomiasis control achievements.

To grasp the status of Oncomelania hupensis snail-infested environments in schistosomiasis endemic areas of Jiangxi Province, and establish the spatial database of snail-infested environments with the administrative village as the unit.The spatial and temporal distributions of the historical snail environments, existing snail environments, and suspicious snail-infested environments were analyzed by the historical data review and field investigations.The distribution of snail-infested environments in Jiangxi Province included two popular types of lakeshore and hills. The O. hupensis snail-infested environments were mainly concentrated in the Poyang Lake area, which accounting for 66.97% of the total snail-infested areas. The potential snail-infested environment area was 204 745.48 hm², among which the potential snail-infested environment areas in the lakeshore and hills were 146 548.58 hm² and 58 196.90 hm², accounting for 71.58% and 28.42%, respectively. The real existing snail area was 83 234.50 hm², among which the real existing snail areas in the lakeshore and hills were 80 890.81 hm² and 2 343.69 hm², accounting for 97.18% and 2.82%, respectively. The compressed snail area was 114 253.30 hm² with a compression rate of 57.85%, of which the compression rates in the lakeshore and hills were 46.51% and 94.97%, respectively. In the four types of snail-infested environments, the areas of Type I, Type II, Type III and Type IV accounted for 55.77%, 25.75%, 13.91% and 4.57% of the total area, respectively.The spatial database of O. hupensis snail-infested environments is established comprehensively and systematically, that will be conducive to tracking and performing the dynamic updates of the data of snails, so as to provide an important technical support for investigation and monitoring in the future.

Objective To investigate the prevalence of Schistosoma japonicum infections in Elaphurus davidianus released to Poyang Lake areas and evaluate the impact of the project of “E. davidianus released to wild environments for natural reproduction and growth” “(E. davidianus return home project”) on the transmission of schistosomiasis in Poyang Lake areas. Methods During the period from April 2018 to December 2019, the population distribution, inhabiting activity and natural reproduction of E. davidianus released to Poyang Lake areas were investigated by means of GPS and artificial observations. The S. japonicum infection was identified in animal feces in E. davidianus inhabitats using a hatching test, and snail distribution was surveyed in E. davidianus inhabiting grass islands using a systematic sampling method. Results A total of 51 E. davidianus were released to the Poyang Lake areas in 2018, which subsequently produced 5 E. davidianus habitats in Yinlong Lake, Longkou, Nanchi Lake, Lianzi Lake and Zhu Lake. E. davidianus was found to predominantly inhibit in grass islands, farmlands and forest lands in hilly regions around the Poyang Lake areas. The natural reproduction rate of E. davidianus was 25% in the habitats in 2019, and the mean density of snails was 0.009 to 0.039 snails/0.1 m² in E. davidianus inhabitats; however, no S. japonicum infection was identified in snails. In addition, the mean densities of wild E. davidianus and bovine feces were 4.6 samples/hm² and 2.1 samples/hm², Conclusions The E. davidianus released to Poyang Lake areas may get infections with S. japonicum, and cause schistosomiasis transmission through fecal contamination in grass islands. The impact on and the prevalence of S. japonicum infection was 4.35% and 13.16% (P = 0.236), respectively; however, the intensities of S. japonicum infections were “+++” and “+”, respectively. Conclusions The E. davidianus released to Poyang Lake areas may get infections with S. japonicum, and cause schistosomiasis transmission through fecal contamination in grass islands. The impact on local schistosomiasis transmission and the response strategy requires to be investigated following the release of E. davidianus to lake regions, to ensure the achievement of the goal of schistosomiasis elimination and the successful implementation of the “E. davidianus return home project” in Poyang Lake areas.