Identification of Tula hantavirus in Pitymys subterraneus captured in the Cacak region of Serbia-Yugoslavia

Background: A typical serum neutralizing antibody responses to prototype strains of Puumala viruses in some patients with hemorrhagic fever with renal syndrome (HFRS) have long suggested the existence of other hantaviruses in the Balkans. Objective: To determine the presence of arvicolid rodent-borne Puumala-like hantaviruses in Yugoslavia. Materials and Methods: Using reverse transcript-polymerase chain reaction, Tula virus RNA was amplified from lung tissues of a European pine vole (Pitymys subterraneus) captured in 1987, following an outbreak of HFRS in the Cacak region of Serbia-Yugoslavia. Results: Sequence analysis of the entire coding region of the S segment and a 948-nucleotide region of the G2 glycoprotein-encoding M segment revealed divergence of approximately 14% from Tula virus strains harbored by European common voles (Microtus arvalis) captured in Central Russia and the Czech Republic. However, nearly complete identity was found in the corresponding deduced amino acid sequences. Moreover, phylogenetic trees constructed by the maximum parsimony and neighbor-joining methods indicated that this Pitymys-borne hantavirus shared a common ancestry with other Tula virus strains. Conclusions: The data demonstrate that Pitymys subterraneus also serves as a rodent reservoir of Tula virus in Serbia-Yugoslavia. To what extent this represents virus spillover from Microtus arvalis warrants further investigation.