[Isolation and identification of Japanese encephalitis virus firstly in Shandong province]

To isolate Japanese Encephalitis virus (JEV) from mosquitoes collected in Jinan city, Shandong province, and to analyse the genotype of new isolated JEV strains and the characteristic of E gene and PrM gene.

Isolate virus from mosquitoes collected in 2008 and identify the isolated virus by biological, serological and molecular biological method. PrM and E segments of new isolated JEV were amplified by RT-PCR, the PCR products were purified and sequencing. Multiple alignment, phylogenetic and amino acid (AA) analysis were carried out by Clustal X (1.83) program, MEGA 3.1 and GENEDOS (3.2).

Total 15,700 mosquitoes were collected including Culex, Armigeres, Aedes, Anopheline. 20 loads were taken at random, one virus strain was isolated from Culex tritaeriorhynchus and identified to be genotype 1 JEV. The homologue of nucleotide and amino acid of E gene between the new isolated JEV and live attenuated vaccine strain SA14-14-2 were 88.0%, 97.2% respectively. There were 14 amino acid differences in E gene between them.

One strain of JEV belonging to genotype 1 was isolated firstly and identified in Jinan city, Shandong province.