Epidemiological Research Of Angistrongyliasis Cantonensis In Tien Lake And Yangzong Hai Watershed Based On GIS Technology

【Objective】Since2003, the Kunming city have been outbreak Angiostrongyliasiscantonensis many times, which is a serious threaten to the local residents and tourismpersonnel health. For the disease has a long incubation period，its hard to trace the sourceof the infection. In order to explore the distribution of Apple Snails,Achatina Fulica andAngiostrongylus cantonensis(A.cantonensis) in Tien Lake and Yangzong Hai watershed andfind out where the Apple Snails comes from, We establish the prediction map of AppleSnails,Achatina Fulica and A.cantonensisin in Yunnan province by the developmental zerotemperature and effective accumulated temperature in GIS. And then, fact-finding missonswere done to make sure whether the areas of Tien Lake and Yangzong Hai watershed arethe Natural foci of A.cantonensis or not. Last, given some advise from control the source ofinfection, cut off the route of transmission, and protect vulnerable populations to preventthe outbreak ofAngiostrongyliasis cantonensis.【Methods】We have collected Average monthly temperature of32Weather stations inYunnan province in recent20years. According to the theory of effective cumulativetemperature,we establish the distributional prediction map of Apple Snails,Achatina Fulicaand A. cantonensis in Yunnan by ArcGIS technology. Based on the forecast figure,theepidemiologica researches were adopted for investigating the types and the distribution oftransmitted hosts of A. cantonensis,infections of the people around Tien Lake andYangzong Hai investigating these areas,and capture the snails randomly from the lake ormarket/restaurant。The enzyme digestion and the lung-microscopy were used to find thesecond stages of Acantonensis in Pomacea canaliculata,the other snails were examined by ehe enzyme digestion.rats captuerd were killed and examin their hearts and lungs,theserum were detected the antibody by enzyme-linked mimunosorbentassay(ELISA).Epidemiological questionnaires were given to the local residents to know theinfections of A.cantonensis,and detected their specific IgG antibodies of A.cantonensis byELISA. Epidata、Excel and SPSS are used to analyse the results【Results】We have predicted the distribution map of A.cantonensis and Pomaceacanaliculata in Yunnan province.It shows that the tempture is Suitable for the growing ofA.cantonensis and Pomacea canaliculata,but not forAchatina fulica.3071snails comes from different area of dianchi/yangzonghai or the market of kunmingwere detected to looking for the larvae of A.cantonensis, which including688Pomaceacanaliculata, no one is positive.426rats has been captured in this survey, including349Rattus norvegicus,16%Rattusflavipectus,2%Mus musclus. We could not find the adults of A.cantonensis in the238pieces of heart and lungs, Serological detection were also negative by ELISA.46.5%of the respondents admitted that they have been eaten the snails which werecooked by Stir-fried or salad.The awareness rate of the related knowledge aboutA.cantonensis is only8.2%. The positive rate of the specific IgG antibodys by the ELISAare about1%(7/690), Positive serum antibody OD value with an average value of0.193(aclinical diagnosis of A. cantonensis disease patients was0.42)but these7people have noNo symptoms such as headache, dizzy or Neck stiff,and4of them does not have the historyof epidemiology. So they could not be diagnosed with Angiostrongyliasis cantonensis.【Conclusion】1. The temperature conditions of Tien Lake and Yangzong Hai basin are suitable for thegrowth and reproduction of Apple Snails and A.cantonensis,but not for suit for AchatinaFulica. Apple Snails has being a invasive alien species in Yangzonghai basin.2. Both of Tien Lake and Yangzong Hai basin are founded Bellamya.3. No A.cantonensis has been found in the host of these two basin,such as snail, shrimp,crayfish. Apple Snails selled in the market are from Guangxi or the Ruili,Honghe,twocity of Yunnan.4. No A.cantonensis has been found in the rats of these two basin. 5. Nearly half of the respondents have been eaten snails, The low awareness rate of therelated knowledge about A.cantonensis is a risk factor for disease outbreaks.6. GIS can be used to predict the distribution of Apple Snails and A.cantonensis, it alsocan be further researched and applicated in the prevention and control the A.cantonensis.