Genetic Diversity of Thottapalayam Virus, a Hantavirus Harbored by the Asian House Shrew (Suncus murinus) in Nepal

Despite the recent discovery of genetically divergent hantaviruses in shrews of multiple species in widely separated geographic regions, data are unavailable about the genetic diversity and phylogeography of Thottapalayam virus (TPMV), a hantavirus originally isolated from an Asian house shrew (Suncus murinus) captured in southern India more than four decades ago. To bridge this knowledge gap, the S, M, and L segments of hantavirus RNA were amplified by reverse transcription polymerase chain reaction from archival lung tissues of Asian house shrews captured in Nepal from January to September 1996. Pair-wise alignment and comparison revealed approximately 80% nucleotide and > 94% amino acid sequence similarity to prototype TPMV. Phylogenetic analyses, generated by maximum likelihood and Bayesian methods, showed geographic-specific clustering of TPMV, similar to that observed for rodent- and soricid-borne hantaviruses. These findings confirm that the Asian house shrew is the natural reservoir of TPMV and suggest a long-standing virus-host relationship.