M gene analysis of atypical strains of feline and canine coronavirus circulating in an Austrian animal shelter.

Coronavirus-positive samples of faeces collected in an Austrian animal shelter from 12 cats and 10 dogs were analysed by reverse transcriptase-pcr with primers amplifying a segment of the M protein gene, and by sequence analysis. In addition, the samples were subjected to S gene typing, using primers that differentiated between feline coronavirus (fcov) types I and II. A phylogenetic analysis of the M gene sequences revealed not only clearly segregating canine coronavirus (ccov) in the dogs, typical ccov sequences and the recently described fcov-like ccov, but also at least two genetic clusters of fcov in the cats, one species-specific, the other more closely related to fcov-like ccov. The M gene sequences of these new feline strains had at most 88 per cent identity with the fcov-like ccov strain 259/01 and only up to 85 per cent with any fcov sequence available in GenBank. In the phylogenetic tree they occupy an intermediate position between feline and canine coronaviruses.