Mosquito diversity (Diptera: Culicidae) and medical importance,in a bird sanctuary inside the flooded forest of Prek Toal,Cambodia

Wild birds have been identified as reservoirs of many pathogens transmissible to humans through bird-biting mosquitoes. Understanding the diversity of vector fauna in bird-conservation areas, is a cornerstone to later develop early detection systems and reduce the risk of emerging disease incidence. Prek Toal is a bird Sanctuary in the Tonle-Sap area in Cambodia hosting the largest migratory bird colony of southeast Asia. The Culicidae fauna was investigated during both dry and rainy seasons. In total, 8,224 mosquitoes from 6 genera and 25 species were collected. The two most represented genera were Anopheles (8 species) and Culex (11 species), while the dominant species was Culex vishnui (58.8%). During the rainy season, 1.6 fold more mosquitoes were caught and the number of species doubled. One of the most notable feature is the absence of any Aedinii mosquito which could be attributed to the low human density around the area, and the large populations of migratory birds. A total of 13 species from 3 genera are reported to be of medical importance. 6 medically-important species were collected in all 3 sites, and are known to bite both wild birds and humans: An. barbirostris, An. campestris, Cx. bitaeniorhynchus, Cx. vishnui, Ma. indiana and Ma. uniformis. One of the most important feature is the over-abundance of Culex vishnui, largely dominant in Prek Toal throughout the seasons and the sites, and being present everywhere in Cambodia. This finding stresses its potentiality to act as bridge vectors in the case of new disease emergence.