Investigation into the naturally infectius status of Hantaviruses in rodents in Yunnan Province,China

Objective To investigate the situation of the natural infection of Hantaviruses(HV) in rodents and offer guidance for the control and prevention of hemorrhagic fever with renal syndrome(HFRS) in Yunnan Province, China. Methods The rodents had been captured by a special trap,the lung tissues of the rodents was taken after identified and stored in-196℃ liquid Nitrogen.HV was detected by direct immunofluorescence assay(DIFA) from the lung tissues of the rodents. Results The 1 303 rodents belonging to 8 species of 5 Genera were captured in 11 counties or cities in Yunnan.Rattus flavipetus and Rattus norvegicus were the dominant species in the residential areas and Apodemus chevrieri and Eothnomys melanogaster were the dominant species in the field.The total natural infection rates of HV in rodents in Xiangyun County,Longling County,Yongsheng County,Lancang County,Xundian County,Yulong County,Jingdong County,Luxi County,Yingjiang County,Dali City and Binchuan County were 7.1%(2/28),6.0%(5/84),5.6%(9/162),5.2%(5/96),5.0%(9/181),3.0%(3/100),2.7%(8/291),2.7%(3/113),2.6%(1/38),2.5%(3/119)and 3.3%(3/91)respectively.The natural infection rate of HV in Rattus flavipetus,Rattus norvegicus,Mus musculus and Rattus nitidus was 3.8%(24/637),5.5%(15/274),4.2%(2/47)and 3.0%(3/100)respectively in the residential areas.The natural infection rate of HV in Apodemus chevrieri,Eothnomys melanogaster,Apodemus draco and Suncus murinus was 2.2%(3/139),1.8%(3/163),0.0%(0/4)and 14.3%(1/7)respectively in the field. Conclusion The rodents were infected naturally and generally by HV in Yunnan Province.There were two types of HV in Yunnan Province,genotype of Seoul circling in the main hosts of Rattus norvegicus and Rattus flavipetus and the genotype of Hantaan circling in the main hosts of Apodemus chevrieri and Eothnomys melanogaster.But,the major type in rodents was the genotype of Seoul circling in the main hosts of Rattus norvegicus and Rattus flavipetus,which were associated with the light and sporadic cases of HFRS in Yunnan Province.