Seewis virus: genetic diversity of a soricid-born hantavirus in Siberia, Russia

Abstract number: P555

Yashina L., Abramov S., Gutorov V., Dupal T., Danchinova G., Panov V., Hay J., Yanagihara R.

Background: Hantaviral antigens were reported more than 20 years ago in tissues of the Eurasian common shrew (Sorex araneus), medium shrew (S. caecutiens) and pygmy shrew (S. minutus), captured in European and Siberian Russia. Recently, a phylogenetically distinct hantavirus, named Seewis virus (SWSV), has been identified in Sorex araneus captured in Switzerland, Hungary and Finland. The Eurasian common shrew is among the most widely dispersed small mammals species in Eurasia, spanning from Europe to Siberia.

Methods: To further clarify the geographic distribution and genetic diversity of SWSV and other hantaviruses harboured by shrews, lung tissues from 29 Sorex araneus, 11 S. tundrensis, six S. minutus and six Sorex sp., captured throughout Western and Eastern Siberia (Teletskoye Lake, Karasuk, Irkutsk and Novosibirsk) in 2007–2008, were analyzed by RT-PCR. To verify the taxonomic identity of the hantavirus-infected shrews, the cytochrome b gene of mtDNA was amplified by PCR.

Results: Hantavirus L- and S-segment sequences were detected in seven S. araneus, two S. tundrensis, and one S. daphaenodon. Overall, the sequences appeared to be genetic variants of SWSV, differing from the prototype mp70 strain from Switzerland by 16–20% at the nucleotide level and 0–2% at the amino acid level. Alignment and comparison of nucleotide and amino acid sequences showed an intra-strain difference of 1–9% and 0–2% for the L-segment and 0–8% and 2% for the S-segment, respectively. Phylogenetic analysis, based on 353- and 837-nucleotides of the L and S segments, showed geographic-specific clustering of SWSV strains. At the same time, at one of the sites SWSV strains from S. araneus showed two separate lineages within the SWSV group.

Conclusions: The detection of SWSV in S. araneus, S. tundrensis and S. daphaenodon in widely separated geographic localities in Siberia demonstrates the vast distribution of SWSV among different but closely related Sorex species. Whether this is a consequence of cross-species virus transmission or co-divergence is unclear. Also, to what extent other sympatric shrews are infected with SWSV warrants further investigation.

Session Details

Date: 16/05/2009
Time: 00:00-00:00
Session name: 19th European Congress of Clinical Microbiology and Infectious Diseases
Location: Helsinki, Finland, 16 - 19 May 2009
Presentation type:
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