Survey On The Distribution Of Mosquito Species And Related Arbovirus In Xinjiang

BackgroundThe occurrence of mosquitoes can date back to the Mesozoic which causes the great harm to animals and humans. It has been a threat to human health from the beginning of the birth of mankind, not only for its biting, but also it can mechanically carries a variety of pathogen and spread pathogen through the sting such as Bancroft filariasis, malaria etc; and mosquitoes can also spread a variety of arboviruses. So far, on a global scale it has been found to spread 537 kinds of arboviruses, of which more than 130 can cause a variety of human and animal diseases. It has become an important worldwide public health problem.Although a little cases of mosquito-borne arboviruses are reported in Xinjiang there is a big difference in mosquito species and arboviruses between in Xinjiang and interal areas of China because of its unique geographical location and environment. In recent years, along with the extensive exploration on arboviruses in Xinjiang, many explorers found that there are potential epidemic risk of some arboviruses including Western equine encephalitis virus, Sindbis virus, Tahyna virus and other mosquito-borne arboviruses. so it is very important to conduct more further survey on the distribution of mosquito species and related arbovirus so as to provide baseline information for the prevention and control of mosquito-borne arboviral diseases in Xinjiang. PurposeTo explore the distribution characteristics of mosquito species in Xinjiang in order to provide a comprehensive baseline data including the distribution of mosquito species, density and seasonal variation. At the same time, a screening on arbovirus in mosquitos was conducted to understand the differences among different kind of mosquito species in Xinjiang so as to provide some foundation for prevention and control of arboviral diseases in Xinjiang. MethodsThe each capital of 14 states and one county in every states were selected by use of cluster random sampling as our survey sites. Light traps was used to collect mosquitoes at night through the cinquefoi points method, and the net method was used to supplement acquisition of mosquito during the day. After collection of mosquitoes the species identification were determined through morphological method, and then the name of mosquito species, the acquisition time, location and the there habitat were recorded. Otherwise, RT-PCR, nested-PCR and real-time PCR were used to detect types of arboviruses. SPSS software was used to enter the data and conduct statistical analysis. Result1.A total of 21 counties in the Xinjiang region were involved in this survey. 3,550 mosquitoes were collected which belonged to 4 genera and 7 species including Culex pipiens, Culex modestus, Aedes caspius, Aedes vexans, Anopheles hyrcanus, Anopheles messeae and Culiseta annulata.2.773 mosquitoes were collected by net method which belonged to 3 genera and 5 species; 2792 mosquitoes were captured by light traps which belonged to 4 genera and 7 species. Mosquito species captured by light trap method were more than that captured by net method. there were some differences in the number constitution of different type of mosquitoes.3.Culex pipiens was the dominant species in xinjiang, accounting for more than 54%, followed by Aedes caspius, accounting for more than 30%. Other mosquito species composition ratio did not exceed 10%. Culex pipiens accounted for more than 63% in southern parts of Xinjiang, and more than 46% in northern parts of Xinjiang with the significant statistical difference between them.4.From July to October there was a peak of mosquito density. The highest density of mosquitos was 11.67/lamp.h in early September, and the lowest density of mosquitoes was 0.89/lamp.h in late October.5.A positive correlation between mosquito density and the average temperature was found, the correlation coefficient R was 0.931, and the regression equation was “Y =-12.684 + 0.814X”.6.All of the arboviruses test of mosquito samples were negative. Conclusion:1. There are seven species in four genera mosquitoes in Xinjiang.Culex pipiens is the dominant species. The highest density of mosquitos is in early September and the correlation coefficient between mosquito density and the average temperature is very high.2. Any positive arboviruses of mosquitos samples are not detected.3.The experts from Chinese Center for Disease Control and Prevention found that Culex pipiens is a medium for the spread of West Nile virus disease in Xinjiang, but it is not detected in this condition of the survey...