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Among other Lyssaviruses, Daubenton's and pond-bat-related European bat lyssavirus type 2 (EBLV-2) can cause human rabies. To investigate the diversity and evolutionary trends of EBLV-2, complete genome sequences of two Finnish isolates were analysed. One originated from a human case in 1985, and the other originated from a bat in 2009. The overall nucleotide and deduced amino acid sequence identity of the two Finnish isolates were high, as well as the similarity to fully sequenced EBLV-2 strains originating from the UK and the Netherlands. In phylogenetic analysis, the EBLV-2 strains formed a monophyletic group that was separate from other bat-type lyssaviruses, with significant support. EBLV-2 shared the most recent common ancestry with Bokeloh bat lyssavirus (BBLV) and Khujan virus (KHUV). EBLV-2 showed limited diversity compared to RABV and appears to be well adapted to its host bat species. The slow tempo of viral evolution was evident in the estimations of divergence times for EBLV-2: the current diversity was estimated to have built up during the last 2000 years, and EBLV-2 diverged from KHUV about 8000 years ago. In a phylogenetic tree of partial N gene sequences, the Finnish EBLV-2 strains clustered with strains from Central Europe, supporting the hypothesis that EBLV-2 circulating in Finland might have a Central European origin. The Finnish EBLV-2 strains and a Swiss strain were estimated to have diverged from other EBLV-2 strains during the last 1000 years, and the two Finnish strains appear to have evolved from a common ancestor during the last 200 years. [ABSTRACT FROM AUTHOR]

We surveyed 12 populations of the montane water vole (Arvicola scherman), previously known as the fossorial form of the water vole A. terrestris, in eastern France for antibodies (immunoglobulin G) to Puumala virus (PUUV), lymphocytic choriomeningitis virus (LCMV), and cowpox virus (CPXV). Antibodies to PUUV were found in 9 (5.5) of 164 voles from 7 populations, antibodies to LCMV were found in 13 (26.0) of 50 voles from 2 populations, and antibodies to CPXV were found in 66 (41.8) of 158 voles from 7 populations. Antibody status to CPXV was statistically associated with the phase of the A. schermanpopulation density cycle and the percentage of grassland areas surrounding the sampling sites. [ABSTRACT FROM AUTHOR]

Sindbis virus (SINV) is a mosquito-borne causative agent of a fever-rash arthritis, Pogosta disease, as verified recently by virus isolation from acutely ill patients. Pogosta disease occurs annually, but it emerges as unique epidemics every 7 years in Finland; over 10,000 patient samples have been analyzed for SINV antibodies, with over 2000 diagnosed acute SINV infections. However, the performance of these serological tests with a large number of samples has not been described before. The aim of the present study was to characterize and evaluate methods developed for the serodiagnostics of SINV infection, suitable for large sample numbers, and to examine the protein-specific responses to the antigen used. We developed SINV IgM and IgG enzyme immunoassays (EIA) using highly purified SINV. The EIAs were compared to hemagglutination inhibition (HI) and neutralization tests. We studied paired samples from 46 acutely ill patients taken at approximately 2-week intervals, with a verified SINV infection confirmed by a fourfold rise in HI antibody titer. The assay cut-off values and specificity were determined with confirmed negative sera. Protein-specific antibody responses were examined with immunoblot assay. The optical density values of the EIAs correlated well with the HI titers. The sensitivities of the IgM and IgG EIAs were 97.6 and 100, and specificities were 95.2 and 97.6, respectively. We consider that a verified serological diagnosis of acute SINV infection requires (1) in addition to a positive IgM result at least a fourfold increase in HI (or IgG) titer between paired sera or (2) a positive IgM result and a negativeborderline IgG result (which excludes old immunity) and specific reaction in HI. Both E1 and E2 glycoproteins of SINV were shown to be recognized by IgM and IgG antibodies early in infection. [ABSTRACT FROM AUTHOR]

The S RNA genome segment of hantaviruses carried by Arvicolinae and Sigmodontinae rodents encodes the nucleocapsid (N) protein and has an overlapping (+1) open reading frame (ORF) for a putative nonstructural protein (NSs). The aim of this study was to determine whether the ORF is functional. A protein corresponding to the predicted size of Tula virus (TULV) NSs was detected using coupled in vitro transcription and translation from a cloned S segment cDNA, and a protein corresponding to the predicted size of Puumala virus (PUUV) NSs was detected in infected cells by Western blotting with an anti‐peptide serum. The activities of the interferon beta (IFN‐β) promoter, and nuclear factor kappa B (NF‐κB)‐ and interferon regulatory factor‐3 (IRF‐3) responsive promoters, were inhibited in COS‐7 cells transiently expressing TULV or PUUV NSs. Also IFN‐β mRNA levels in IFN‐competent MRC5 cells either infected with TULV or transiently expressing NSs were decreased. These data demonstrate that Tula and Puumala hantaviruses have a functional NSs ORF. The findings may explain why the NSs ORF has been preserved in the genome of most hantaviruses during their long evolution and why hantavirus‐infected cells secrete relatively low levels of IFNs. J. Med. Virol. 79:1527–1536, 2007. © Wiley‐Liss, Inc. [ABSTRACT FROM AUTHOR]