Virological surveillance on hemorrhagic fever with renal syndrome in Hunan province in 2006

Objective To understand the rate of viral carrying status among rodents as well as genotypes and distribution of Hantaviruses(HV) isolated in Hunan province.Methods With DFA,the HV antigen in lung tissues of rodents was detected.The total viral RNA was extracted from the lung tissues of the HV infected rats and amplified with reverse transcrition-polymerase chain reaetion(RT-PCR),using the HV genotype specific primers.The amplified genes were then sequenced and subjected to genotyping and homologic analysis.Results The average density of rodents was 3.15 % and the virus carrying rate among rodents was 1.31%.Data from genotype analysis showed that the HV isolated from seven lung specimens taken from Rattus norvgicus,Apodernus agraius,Mus musculus,Rattus flavipectus among indoor rodents in Shaodong and Liuyang belonged to HV typeⅡ(SEOV),and one isolated from Apodemus agraius in Shaungfen belonged to HV typeⅠ(HTNV) among outdoor rodents.Six strains were sequenced successfully and the homology between six srains was 88.3%-100%.The homology of HN1,HN2,HN4, HN6 came from Liuyang and the HN7 and HN8 from Shaodong were both 100% while the homology between L99 and the strains from Liuyang and Shaodong were 94.4% and 88.3% respectively.Conclusion HV typeⅡ(SEOV) and the HV typeⅠ(HTNV) were all existed in Hunan province while SEOV was the main genotype.