ABSTRACT
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.
ABSTRACT
Objective To understand the present situation of the chronic schistosomiasis patients'knowledge,attitude and practice on schistosomiasis control in Nanchang City. Methods The knowledge,attitude and values on schistosomiasis control of 523 chronic schistosomiasis patients in Nanchang County,Jinxian County and Xinjian District in the Poyang Lake District were investigated with questionnaires. And the accuracy rates of the knowledge,attitude and practice among the patient groups of different counties,genders,age groups,occupations and educational levels were analyzed. Results The accuracy rates of the knowledge,attitude and practice of patients on schistosomiasis control were 95.76%,82.80%,and 81.73% in Nanchang County;91.37%,93.32%,and 76.48%in Jinxian County;88.25%,67.56%,and 49.40%in Xinjian District. In the accuracy rates of knowledge,attitude and practice,the differences among the three counties (districts) were statistically significant (χ2=57.511-301.378,all P<0.05). Conclusions The accuracy rates of chronic schistosomiasis patients'attitude and prac-tice on schistosomiasis control in Nanchang City remain low. Therefore,the intensity of attitude and practice intervention should be strengthened in the Poyang Lake District in order to enhance the self-protection awareness of the patients.
ABSTRACT
Objective To evaluate the long?term effect of the comprehensive control strategy for schistosomiasis with empha?sis on infectious source control in marshland?type endemic areas of Poyang Lake. Methods Three heavy endemic villages with schistosomiasis in the lake areas were selected as pilots for the comprehensive control strategy which included replacing bovine with tractors and forbidding grazing on marshlands. The data of schistosome infections of residents and Oncomelania hupensis snails were collected and analyzed statistically from 2009 to 2014. Results There were no patients with schistosomiasis through feces examinations in the 3 pilot villages. The average density of live snails in Niuzhou marshland showed a decline trend and the density was stable in Liulingwei marshland. There were no infected snails in the 2 marshlands and no schistosome adult worms were found in the sentinel rats Conclusion The implantation of the comprehensive control strategy for schistosomiasis with em?phasis on infectious source control can control the prevalence of schistosomiasis during a long period.
ABSTRACT
Objective To understand the characteristics of schistosome cercarial infested water contact of residents in Poyang Lake endemic areas after the operation of Three Gorges Project,so as to provide the evidence for formulating a well-directed con-trol strategy. Methods The residents in two villages in schistosomiasis endemic areas were selected and surveyed for their activi-ties of infested water contacts by questionnaire. Results The proportion and frequency of infested water contacts of residents in Poyang Lake region were high and the average rate of infested water contacts was 69.77%,and 98.96%of infested water contacts occurred in spring,summer and autumn. The main ways of infested water contacts were fishing/swimming/playing for adult men, washing clothes/fishing for adult women,and swimming/playing for school children,respectively. The rates of infested water con-tacts were 73.33%,71.63%and 61.87%in adult men,women and school children,respectively. The frequencies of infested water contacts>1 time/week,1 time/week-1 time/month,and<1 time/month were 62.61%,23.74%and 13.66%respectively. Conclu-sions The infested water contacts mainly occurs in spring,summer and autumn,and the main way of infested water contacts was fishing. Farming and mowing grass,which had been the primary way,now become the secondary way for the adult residents.