ANTIGENIC AND MOLECULAR CHARACTERIZATION OF HANTAVIRUS ISOLATES FROM CHINA

Hemorrhagic fever with renal syndrome (HFRS) is caused by certain viru ses in the genus Hantavirus, family Bunyaviridae, and is a major publi c health problem in China. By using molecular and serological tests, w e characterized 15 hantaviruses isolated either from patients with HFR S or from rodents captured in endemic areas of China. By cross plaque- reduction neutralization tests performed with rabbit immune sera, we i dentified two serologically distinct groups of viruses, comprised of t hose related to Hantaan virus, and those related to Seoul virus. To st udy the genetic relationships among these viruses, we amplified a 330 base pair region of the medium (M) genome segment of each isolate by r everse transcription and polymerase chain reaction (PCR) and compared the nucleotide sequences to those of other, well-characterized hantavi ruses. In addition, we PCR-amplified and analyzed the entire coding re gion of the small (S) genome segment of each isolate by restriction en zyme digestion with a battery of enzymes. The results of our genetic a nalyses of both the M and S segments of these isolates confirmed our s erological data, indicating that Hantaan and Seoul viruses co-circulat e in endemic disease regions of China. We constructed a phylogenetic t ree based on multiple alignment of the partial M segment sequences. Th e resulting dendrogram distinguished three genetic subtypes of Hantaan viruses and one type of Seoul virus.