Geographical clustering of Hantavirus isolates from Apodemus agrarius identified in the Republic of Korea indicate the emergence of a new Hantavirus genotype.

• Hantaan virus showing geographical clustering in the Republic of Korea. • Geographical variation presenting genetic divergence of Hantaan virus. • Genetic divergence indicates the emergence of new Hantavirus strains. • High hantavirus prevalence and seasonal variation in A. agrarius captured from Jeju. Several studies on hantavirus evolution have shown that genetic reassortment plays an important role in the evolution and epidemiology of this disease. To understand the genetic epidemiology of human hantaviruses, samples from rodent reservoirs were subjected to reverse-transcription nested polymerase chain reaction (RT-N-PCR) targeting the L - and S-segments of the hantavirus genome. Positive isolates from Gwangju, Boseong-gun (Jeollanam-do Province), and Jeju Island were confirmed as Hantaan virus using DNA sequencing. Phylogenetic analysis showed that all isolates grouped together as Hantaan virus but with each region forming a distinct cluster. In addition, these three clusters were distinct from other Hantaan isolates reported in previous studies from Korea and its neighboring countries China and Russia. This suggests Hantaan viruses exhibit a considerable degree of geographical clustering, and there may be a novel Hantaan genotype in southwestern ROK. This study helps expand our knowledge regarding the emergence of new hantavirus strains and their degree of geographical variation. Hantaan virus, a pathogenic prototype hantavirus carried by Apodemus agrarius , is found throughout China, Russia, and Korea. Here, we examined the genetic diversity of hantaviruses to expand our knowledge regarding the emergence of new hantavirus strains and their degree of geographical variation. We found that hantaan viruses show a considerable degree of geographical clustering, which may allude to the development of a new genotype variant in the southwestern region of the ROK. [ABSTRACT FROM AUTHOR]