ABSTRACT
Objective To isolate and identify Banna virus(BAV)from mosquitoes collected in Mengla county of Yunnan province.Methods Mosquito samples were collected in houses and stock yards in Mengla county,2008.Mosquitoes were homogenized and incubated onto both C6/36 and BHK21 cells.The new isolate was identified by using ELISA and RT-PCR.The sequences of segment 5.8 and 11 of BAV were amplified by RT-PCR and determined.Phylogenetic analysis on the new BAV were performed using MEGA4 program.Results 1731 mosquitoes representing 7 species were collected with one strain of BAV isolated and identified.Phylogenetic analysis based on sequences of segment 8 showed the new isolate was closed to BAV strain isolated in Yunnan,but segment 11 sequence was closed to Vietnam strain.Conclusion Results of phylogenetic analysis implied that the BAV re-assortment might have been occurred both in Chinese and Vietnam strains.
ABSTRACT
Objective To identify the Banna viruses isolated in northwestern part of Yunnan prov-ince in order to make the difference clear between the isolates and other Banna viruses isolated in other parts of Yunnan. Methods Three isolates of Banna vires isolated in 2005 and 2006 were identified by morpholo-gy, RNA-PAGE profile and molecular biologic method. Nueleotide and amino acid sequences of segment 12 of the 3 isolates were sequenced and analyzed. Results Three Banna viruses were isolated from mosquitoes collected in northwestern part of Yunnan during 2005 and 2006. Electron microscopy study showed that they are spherical with a diameter of 70 nm, no envelope but two layers of eapsid. It was found that the genome of the 3 isolates composes of 12 segments presenting band profile of 6-6 in RNA-PAGE. Nueleotide acid se-quence analysis about segment 12 showed that the identity was 99% between the 3 new isolates, 98% and 90% between the 3 isolates and the strains isolated in other parts of Yunnan, China and Indonesia, respec-tively. Phylogenetie analysis based on segment 12 gene showed that 3 new isolates clnstered in the same branch with the viruses isolated in other parts of Yunnan. The same difference of amino acids was found between Banna viruses isolated in China and Indonesia strains in the analysis of segment 12. Conclusion Banna virus strains were firstly isolated from mosquitoes collected in northwestern part of Yunnan province. Nueleotide acid sequence analysis of the 3 new isolates showed higher identity with strains isolated in other parts of Yunnan.
ABSTRACT
Objective To isolate and identify arboviruses from mosquito pools in some regions of Liaoning province.Methods Mosquitoes were collected from Shenyang,Yingkou,Panjin,Jinzhou and Dandong cities of Liaoning province in 2006.Viruses were isolated by inoculating the specimens onto C6/ 36 and BHK-21cells.The new isolates were identified using serological and molecular biological methods.Results 5410 mosquitoes were collected from the five cities in total.Three isolates produced CPE in C6/ 36 cell and five isolates produced CPE in both C6/36 and BI-IK-21 cell.Three isolates (LN0684,LN0688 and LN0689) were identified as Banna virus and one isolate (LN0636) was identified as Getah virus.Phylogenetic analysis showed that the three Banna virus strains were clustered into the same evolution branch as the other Chinese isolates.The identity of nucleotide sequence was between 91.2% and 94.7%,compared with other Banna virus strains.The new isolated Getah virus was clustered into the same branch with the strain of South Korea (swine).The identity of nucleotide sequence was 99.2%,when comparing with the strain of South Korea and was 95% to 99% with the strains fi'om Russia,mainland of China and Taiwan region.Conehmion Eight virus isolates,including three Banna virus,one Getah virus and four unknown virus strains were isolated from mosquitoes in Liaoning province.Banna virus and Getah virus were reported for the first time in Liaoning province,while Getah virus showed the highest nucleotide homology with the South Korea strains.