<i>Feline coronavirus</i> isolates from a part of Brazil: insights into molecular epidemiology and phylogeny inferred from the <i>7b gene</i>

Abstract

The Feline coronavirus (FCoV) can lead to Feline infectious peritonitis (FIP), which the precise cause is still unknown. The theory of internal mutation suggests that a less virulent biotype of FCoV (FECV) would lead to another more pathogenic biotype (FIPV) capable of causing FIP. In this work, the 7b gene was amplified from 51 domestic cat plasma samples by semi-nested PCR and tested through phylogenetic and phylogeographical approaches. The 7b gene of Brazilian isolates displayed high conservation, a strong correlation between the geographic origin of the viral isolates and their genealogy, and its evolution was possibly shaped by a combination of high rates of nucleotide substitution and purifying selection.

Origin and transmission of Feline coronavirus type I in domestic cats from Northern Italy: a phylogeographic approach

“…The significant geographical structure that was observed by our analysis, with the majority of FCoV sequences segregating on the basis of their geographical origin, has been also recently reported in another study in Brazil (Myrrha et al, 2019). In the last decade, the presence of different significant subclades with few FCoV type I sequences collected from the same country (and from cities close to each other in case of Italian sequences), in a restricted period of time, likely represent recent networks in the local circulation of the virus.…”

“…Our results also suggest that in the last decade FCoV transmission seem to rely on different areas from which the virus spreads. A similar result was not reported in Brazil (Myrrha et al, 2019), where the FCoV 7b gene was used for the phylogeographical analysis showing high conservation of sequences. It is likely that the use of a highly variable gene, such as the S gene, allows a deeper insight of the pattern of spread of FCoV in recent years.…”

“…The significant migration link that was observed by our phylogeographical reconstruction between the US and Germany during 1974-1995 is in agreement with the information on the first reports of FIP in Germany years after the US (Landes et al, 1984) and suggests that the virus likely moved from the US to Europe where it reached Germany. Evidence of North America being the source of introduction of FCoV in other countries has also been recently reported in Brazil (Myrrha et al, 2019). FCoV introduction in countries is likely by animal movements.…”

“…For a better understanding of pathways of infection dispersion, a phylogeographical analysis that allows reconstruction of the most probable place of origin of infections and flow of geographic spread of viruses has been developed (Lemey et al, 2009;Drummond et al, 2012). This approach has been used to reconstruct spatial and temporal J o u r n a l P r e -p r o o f dispersion of some highly variable viruses but, to our knowledge, has been applied only in one recent study providing insights into the origin of FCoV in Brazil (Myrrha et al, 2019).…”

Clinical and molecular aspects of veterinary coronaviruses

“…The main distinction between them is associated with their differences in the S gene sequence and antibody neutralization properties ( Hohdatsu et al, 1991 ; Jaimes et al, 2020 ; Shiba et al, 2007 ; Tekes and Thiel, 2016 ). Serotype FCoV-I is 80-90% more prevalent than FCoV-II worldwide ( Amer et al, 2012 ; Kummrow et al, 2005 ; Myrrha et al, 2019 ). The emergence of serotype FCoV-II has involved recombination events between the S and M genes of FCoV-I and CCoV-II ( Herrewegh et al, 1998 ; Terada et al, 2014 ).…”