Isolation and Identification of Arbovirus from the Sentinel Herds in Jinghong City,Yunnan Province,China in 2019

The purpose of this study was to understand the prevalence of arboviruses in Jinghong city,Yunnan province.Three sentinel cattle were set up in Menghan township of Jinghong city in 2019,blood samples were collected regularly for isolation and identification of arboviruses,a total of 7 virus isolates were obtained.Viral nucleic acid were identification by RT-PCR,and the results showed that two strains of epidemic hemorrhagic fever virus (EHDV) with serotypes of 6 and 7,two strains of bluetongue virus (BTV) with serotypes 4 and 5,D’Aguilar virus (DAV) serotype in one strain of PALV and two unidentified circoviruses were isolated,respectively.The ORF region of virus Seg-2 and Seg-3 sequences was compared and analyzed,all the 7 regional strains of the virus were Eastern,which was most closely related to strains in Japan,Australia and India.The blood and serum of three sentinel animals were tested by viral nucleic acid and serum neutralization test,which proved that all three animals were infected with the corresponding virus.When animals were infected with the virus,specific antibodies in the serum rise rapidly,it reached peaks 3 to 4 weeks later and could remain at this level for a long time.However,the content of viral nucleic acid in the blood decreased rapidly after reaching the peak from 2 to 4 weeks.The isolation,sequence characteristics and infection characteristics of Jinghong arboviruses in animals were reported in this study,the results provided data support for further understanding of local bovine arboviruses.At the same time,7 strains of virus were isolated from 3 cattle,suggesting that there might be more arboviruses in the area.