Background: To survey arboviruses in Yunnan province.
Methods: Mosquitoes were collected from Yunnan Province in 2002 and 2004. Virus strains were isolated by the inoculation of homogenates of the mosquitoes onto BHK cell line. The isolated strains and their molecular biological characteristics were identified by real-time PCR, reverse transcription-polymerase chain reaction (RT-PCR) and immunofluorescent antibody technique.
Results: Twelve strains of viruses producing CPE in BHK cells were isolated from 4810 mosquitoes. All the 12 isolates were identified to be Japanese encephalitis viruses. Genotype analysis showed the new virus (DL-0437 strain) belonged to genotype III.
Conclusion: Twelve strains of Japanese encephalitis viruses were isolated from mosquito pools collected in Yunnan. It was the first isolation of genotype III Japanese encephalitis viruses in Yunnan Province in recent years.