2016—2020年扬州市江都区江滩野鼠及野粪血吸虫感染监测

目的 了解有螺江滩野鼠及野粪血吸虫感染情况,探讨敏感、有效的监测方法,减少血吸虫病传播潜在风险。 方法 每年选择疫情风险较高的江滩,采取投放鼠夹法捕捉野鼠,每次每块滩地投放鼠夹200只,全年4次,统计鼠夹回收率和捕获率。对捕获的野鼠逐只解剖,观察血吸虫感染情况。采用20 m×20 m系统抽样或结合环境抽样法,收集有螺江滩上的野粪;采用塑料杯顶管孵化法检测野粪血吸虫阳性情况。 结果 2016—2020年共在5个有螺江滩累计投放鼠夹9 820只次,回收鼠夹9 643只次,回收率为98.20%。累计捕获野鼠215只,捕获率为2.23%;解剖发现阳性野鼠14只,阳性率为6.51%;其中2016年阳性率为8.33%,2017年阳性率为34.62%。2016年屏江东滩野鼠阳性率为8.33%;2017年阳性率为26.67%,双港滩阳性率为55.56%。累计开展野粪调查20次,检获野粪156 份,重量2 433 g;其中检获羊粪136份,占野粪总数的87.18%。经病原学检测,均为阴性。 结论 扬州市江都区有螺江滩存在野鼠感染血吸虫,人、畜活动较多,需加强监测,完善监测预警体系,开展风险评估。

Surveillance of Schistosoma japonicum infection among wild rodents and wild fecal on river beaches in Jiangdu District,Yangzhou City, 2016-2020

Objective To understand the infection of Schistosoma japonicum (S. japonicum) among wild rats and wild fecal on river beaches with Oncomelania snails, to explore sensitive and effective monitoring methods, and to reduce the potential risk of schistosomiasis transmission. Methods We selected river beaches with high epidemic risk every year and caught wild rats by setting rat traps. 200 rat traps were set on each beach each time, with four times a year. The recovery rate and capture rate of the rat traps were counted. The captured wild rats were dissected one by one to observe the infection of S. japonicum. We adopted 20 × 20m systematic sampling or combined with environmental sampling method to collect wild manure on beaches with Oncomelania snails. The status of S. japonicum positive in wild feces was detected by hatching test. Results From 2016 to 2020, a total of 9,820 rat traps were set on 5 river beaches with Oncomelania snails, and 9,643 rat traps were retrieved, with the recovery rate of 98.20%. A total of 215 wild rats were captured, with the capture rate being 2.23%. 14 positive rats were detected through dissection experiments, with the positive rate of 6.51%. The positive rate was 8.33% in 2016 and 34.62% in 2017. The positive rate of wild rats in eastern beach of the Pingjiang was 8.33% in 2016 and 26.67% in 2017. The positive rate in Shuanggang beach was 55.56%. We accumulatively conducted 20 surveys on wild manure, and obtained 156 aliquots of wild feces weighing 2,433g, including 136 aliquots of feces from goats and accounting for 87.18% of the total wild feces. All were negative by pathogenic test.Conclusion There were wild rats infected with S. japonicum on river beaches with Oncomelania snails in Jiangdu District of Yangzhou City, and many human and livestock activities were found. It is necessary to strengthen monitoring, improve the surveillance and early warning system and carry out risk assessment.