Seewis virus, a genetically distinct hantavirus in the Eurasian common shrew (Sorex araneus)

Abstract

More than 20 years ago, hantaviral antigens were reported in tissues of the Eurasian common shrew (Sorex araneus), Eurasian water shrew (Neomys fodiens) and common mole (Talpa europea), suggesting that insectivores, or soricomorphs, might serve as reservoirs of unique hantaviruses. Using RT-PCR, sequences of a genetically distinct hantavirus, designated Seewis virus (SWSV), were amplified from lung tissue of a Eurasian common shrew, captured in October 2006 in Graubünden, Switzerland. Pair-wise analysis of the full-length S and partial M and L segments of SWSV indicated approximately 55%-72% similarity with hantaviruses harbored by Murinae, Arvicolinae, Neotominae and Sigmodontinae rodents. Phylogenetically, SWSV grouped with other recently identified shrew-borne hantaviruses. Intensified efforts are underway to clarify the genetic diversity of SWSV throughout the geographic range of the Eurasian common shrew, as well as to determine its relevance to human health.

Figure 1

Phylogenetic relationships between Seewis virus (SWSV) and representative rodent- and soricid-borne hantaviruses, using the GTR+I+G model of evolution. Maximum likelihood phylogenies, based on full-length coding alignments of S, M and L segments, incorporating 1,290, 250 and 3,300 nucleotides, respectively, of SWSV strain mp70, shown in relationship to representative Murinae rodent-borne hantaviruses, including Hantaan virus (HTNV 76–118, NC_005218, NC_005219, NC_005222), Dobrava virus (DOBV Greece, NC_005233, NC_005234, NC_005235), and Seoul virus (SEOV 80–39, NC_005236, NC_005237, NC_005238); Arvicolinae rodent-borne hantaviruses, including Tula virus (TULV M5302v, NC_005227, NC_005228, NC_005226), Prospect Hill virus (PHV PH-1, Z49098, X55128, EF646763) and Puumala virus (PUUV Sotkamo, NC_005224, NC_005223, NC_005225); and Sigmodontinae and Neotominae rodent-borne hantaviruses, including Andes virus (ANDV Chile 9717869, NC_003466, NC_003467, NC_003468) and Sin Nombre virus (SNV NMH10, NC_00521, NC_005215, NC_005217). Also included are Camp Ripley (RPLV MSB89863, EF540771, EF540774) from the northern short-tailed shrew (Blarina brevicauda), Cao Bang virus (CBNV TC-3, EF543524, EF543525, EF543526) from the Chinese mole shrew (Anourosorex squamipes), Tanganya virus (TGNV Tan826, EF050454, EF050455) from the Therese shrew (Crocidura theresae), and Thottapalayam virus (TPMV VRC-66412, AY526097, EU001329, EU001330) from the Asian house shrew (Suncus murinus). The numbers at each node are bootstrap support values (expressed as the percentage of replicates in which the node was recovered), as determined for 100 ML replicates using RAxML [25]. The scale bar indicates 0.1 nucleotide substitutions per site. GenBank accession numbers for SWSV: S (EF636024); M (EF636025) and L (EF636026).