Abstract:
Objective To analyze the potential risk of infection sources during the consolidation phase of schistosomiasis elimination in Lushan County (a mountainous region) of Sichuan Province, and to provide prevention and control strategies for the consolidation of schistosomiasis elimination achievements in mountainous areas.
Methods In 2024, one to two villages with historically severe epidemics were selected in the heavily endemic townships of Lushan County as monitoring sites to carry out monitoring for wild animal feces, domestic animals, wild rats, free-roaming dogs, local residents, and mobile populations. Follow-up monitoring for previously infected individuals was carried out in Caoping Village of Siyan Town. Statistical analyses were performed to assess the risks associated with infection sources.
Results A total of 115 fecal samples from 13 species of wildlife were incubated, with all negative. Blood tests were conducted on 492 cattle, 34 sheep, and 261 dogs, with all negative. A total of 2 520 rodent traps were set, capturing 67 wild rats with a capture rate of 2.66%, and no positive wild rats were found upon dissection. The activity track of 25 loose dogs was 2 212 meters at the farthest, 236 meters at the nearest, and 744 meters on average. a total of 68 wild droppings (all dog feces) were picked up along the way, with all negative. Blood tests were performed on 3 540 local population, yielding 39 blood-positive cases with a blood positive rate of 1.1%. Fecal examinations were conducted on 193 individuals, with all negative. A total of 315 blood tests were performed on the mobile population, identifying 1 positive case with a blood-positive rate of 0.32%. One person received a fecal examination, with zero positive. A follow-up survey of 505 previously infected individuals revealed 5 blood-positive cases, with a positive rate of 0.99%. Fecal examinations were conducted on 15 individuals, with all negative.
Conclusion In this investigation, no local or imported sources of schistosomiasis transmission were found. However, there was a wide variety and a large number of potential sources of infection in the local area. It is necessary to actively explore regional monitoring models for schistosomiasis elimination flexibly adjust prevention and control strategies according to local conditions, achieve precise prevention and control, and consolidate the achievements of elimination.