Objective To investigate the distribution patterns of mosquitoes and mosquito-borne viruses in Dehong prefecture,Yunnan province,China. Methods Mosquito samples were collected using the mosquito traps from five counties of Dehong prefecture on July,2007 and 2010. Mosquitoes were cell cultured for viral isolation,and positive isolates were identified using RT-PCR and sequence analysis. Results A total of 43 634 mosquitoes comprised of 29 species representing six genera were collected. Culex tritaeriorhynchus and Anopheles sinensis comprised 78.69% and 14.77% of the total. Six strains of viruses were isolated from the mosquito pools. RT-PCR and phylogenetic analysis revealed three strains from Cx. tritaeriorhynchus,identified as genotypeⅠJapanese encephalitis virus(JEV). One strain was identified from Cx. tritaeriorhynchus,as Getah virus (GETV). Two strains isolated from Cx. tritaeriorhynchus and Anopheles vagus were identified as Culex pipiens pallens Densovirus(CppDNV). Conclusion Cx. tritaeriorhynchus had been the major species of mosquitoes and mainly transmitting vector of mosquito-borne viruses in Dehong prefecture. GenotypeⅠJEV,GETV and CppDNV were the vectors causing transmission of mosquitoe-borne diseases in this area. Data from phylogenetic analysis showed that these newly discovered isolates seemed to have had close relationship with those viruses previously circulating in Yunnan and other provinces of China.

OBJECTIVETo investigate the distribution patterns of mosquito and mosquito-borne viruses in Dehong prefecture, Yunnan province, China.

METHODSMosquito samples were collected using the mosquito traps from five counties of Dehong prefecture on July, 2007 and 2010. Mosquito were cell cultured for viral isolation, and positive isolates were identified using RT-PCR and sequence analysis.

RESULTSA total of 43 634 mosquito comprised of 29 species representing six genera were collected. Culex tritaeniorhynchus and Anopheles sinensis comprised 78.69% and 14.77% of the total. Six strains of viruses were isolated from the mosquito pools. RT-PCR and phylogenetic analysis revealed three strains from Cx. tritaeniorhynchus, identified as genotype I Japanese encephalitis virus (JEV). One strain was identified from Cx. tritaeniorhynchus, as Getah virus (GETV). Two strains isolated from Cx. tritaeniorhynchus and Anopheles vagus were identified as Culex pipiens pallens Densovirus (CppDNV).

CONCLUSIONCx. tritaeniorhynchus had been the major species of mosquito and mainly transmitting vector of mosquito-borne viruses in Dehong prefecture. Genotype I JEV, GETV and CppDNV were the vectors causing transmission of mosquito-borne diseases in this area. Data from phylogenetic analysis showed that these newly discovered isolates seemed to have had close relationship with those viruses previously circulating in Yunnan and other provinces of China.

Alphavirus ; isolation & purification ; Animals ; Arboviruses ; classification ; isolation & purification ; China ; Culicidae ; virology ; Disease Vectors ; classification ; Encephalitis Virus, Japanese ; isolation & purification