Nucleotide Sequence and phylogenetic Analysis of Hantaviruses Isolated from Patients with Hemorrhagic Fever with Renal Syndrome (HFRS) in Korea

ABSTRACT

Eleven hantavirus isolates were obtained by innoculation of viremic blood, urine, or autopsy tissue specimens from ten HFRS patients, and sera were obtained from five patients with HFRS. The disease was diagnosed by clinical manifestations and indirect immunofluorescent antibody technique. We obtained 6 hantaviruses from gene bank. So, we analyzed 22 hantavirus samples to elucidate the genetic diversity. The hantaviral RNAs were extracted and 365 base-pair complementary DNAs of M segment were obtained by reverse transcriptase polymerase chain reaction (RT-PCR) and 326 base-pair by nested PCR. The nucleotide sequences of amplified cDNA fragments were determined by the direct sequencing method using automatic DNA sequence analyzer. We got full M segment sequences of 28 reported hantaviruses with medline searching, and aligned them with our 22 samples, and the phylogenetic analysis for nucleotide and amino acid sequences were done by the Clustal method. The nucleotide and amino acid sequences of Hantaan virus 17 samples showed high (above 90%) homology with 76-118 strain, but 2 samples showed significant differences with 76-118 strain and with other 17 samples. The 3 Seoul virus samples showed high intraspecies differences in 1 sample, and showed singnificant differences with SR-11 strain. In phyogenetic tree analysis, Puumala virus and Hantavirus pulmonary syndrome viruses showed high homology, but Hantaan and Seoul viruses showed significant genetic diversity among strains. In conclusion, hantaviruses isolated from HFRS patients showed genetic diversity compared with those isolated from rodent hosts.