| West Nile Virus (WNV) , a member of the Japanese encephalitis virus serogroup in the family Flaviviridae, has the potential to cause febrile illness, encephalitis, and occasional death in human. In nature, this virus is circulated among mosquitoes and birds and enzootic in Africa, Asia, and southern /central Europe. The virus emerged in New York during the summer of 1999 which had bringing the attention of the world to the emerging of WNV. Nowadays, vector controls are still the primary method to prevent and control the emergence of WNV, the study on the transmitting of WNV by vector mosquitoes became important. At present, it was found that some mosquito species can transmit WNV, even geographic strains of one species have different role in the transmission of WNV, but little is known about the potential for mosquito species in china to serve as a vector for this virus. Furthermore, some research showed that WNV can be transmitted transovarially by mosquitoes, but the role of dispaused eggs in the conservation of WNV is still not investigated.In the present study, Ae. aegypti and four geographic strains of Ae. albopictus were used to be infected orally with WNV. Incubated (28℃, 75%RH, L/D=16/8) 12 to 14 days, they were allowed to transmit virus by bite. RT-PCR, virus isolation with C6/36 and IFA were used to detect the virus in mosquitoes and the bloods of chicken bitted by infected mosquitoes, and calculated the rates of infection and transmission of tested mosquitoes. In addition, eggs from 3 gonotrophic cycles of infected Ae.albopictus were collected, one of the groups were subjected to a simulated overwintering condition with a low temperature, short photoperiod (4℃,L/D=8/16) and desiccate environment (50%RH, 75%RH) to induce them into diapause situatuation, another group of eggs were transferred to normal laboratory condition with desiccation (25℃, 75% RH, L/D=14/10). Both RT-PCR and isolation with C6/36 cell were used for assay of the WNV...
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