Feline bocavirus-1 associated with outbreaks of hemorrhagic enteritis in household cats: potential first evidence of a pathological role, viral tropism and natural genetic recombination

Abstract

Feline bocavirus-1 (FBoV-1) was identified in cats from different households with hemorrhagic enteritis during outbreaks of an unusual clinical presentation of feline panleukopenia virus (FPLV) in Thailand. Use of polymerase chain reaction revealed the presence of the FBoV-1 DNA in several tissues, suggesting hematogenous viremia, with the viral nucleic acid, detected by in situ hybridization (ISH), was localized in intestinal cells and vascular endothelium of intestinal mucosa and serosa, and in necrosis areas primarily in various lymph nodes while FPLV-immunohistochemical analysis revealed viral localization only in cryptal cells, neurons, and limited to leukocytes in the mesenteric lymph node. Full-length coding genome analysis of the Thai FBoV-1 strains isolated from moribund cats revealed three distinct strains with a high between-strain genetic diversity, while genetic recombination in one of the three FBoV-1 strains within the NS1 gene. This is the first report identifying natural genetic recombination of the FBoV-1 and describing the pathology and viral tropism of FBoV-1 infection in cats. Although the role of FBoV-1 associated with systemic infection of these cats remained undetermined, a contributory role of enteric infection of FBoV-1 is possible. Synergistic effects of dual infection with FPLV and FBoV-1 are hypothesized, suggesting more likely severe clinical presentations.

Feline Parvovirus Seroprevalence Is High in Domestic Cats from Disease Outbreak and Non-Outbreak Regions in Australia

“…The high rate of FPV seropositivity among cats not known to be vaccinated also indicates that most infections were likely subclinical or caused only mild disease. The development and severity of FPL in naïve cats is dependent on the interplay of multiple host factors (e.g., age, immune status) and viral factors (e.g., inoculating dose), as well as the presence, in some cases, of co-pathogens including intestinal parasites and other enteric viruses (e.g., bocaviruses) [40,41]. Since FPV is profoundly immunosuppressive in cats, opportunistic pathogens, such as bacteria and fungi, can also contribute to the development of severe clinical disease [42,43].…”

TaqMan-based real-time polymerase chain reaction assay for specific detection of bocavirus-1 in domestic cats

“…Bocavirus (BoV) belongs to the subfamily Parvovirinae and is a non-enveloped, linear, single strand DNA (ssDNA) virus with a genome of 5.4 kb [ [1] , [2] , [3] , [4] , [5] ]. BoV has three open reading frames (ORF), namely ORF1, ORF2, and ORF3, encoding non-structural protein (NS1), structural viral capsid proteins (VP1 and VP2), and nuclear phosphoprotein (NP1).…”

“…Feline bocaviruses (FBoVs) are divided into three types, and they belong to the genus Carnivore bocapavovirus 3–5 [ 4 ]. FBoV-1 was discovered in 2012 in fecal, kidney, nasal, and blood samples from clinically asymptomatic cats in Hong Kong [ 8 ].…”

Molecular epidemiology and genome analysis of feline morbillivirus in household and shelter cats in Thailand

“…RNA viruses possess a high mutation rate as a result of viral RNA polymerases lack a proof-reading property, then allowing rapid adaptations to various selection pressures [ 28 , 31 ]. Moreover, recent studies have shown evidence of other morbilliviruses undergoing selective pressure, such as the negative and positive selective pressure for canine distemper virus and measles virus, respectively [ 3 , 32 ]. In this study, we found that overall the FeMV evolution has undergone a negative selective pressure, but positive selection sites were observed, with the highest frequency in the P gene, followed by in the H, N and F genes.…”

“…To detect any potential recombination sites in the FeMV-Thai strains, a panel of previously described statistical methods was applied [ 32 ]. Briefly, each recombination analysis, including RDP, GENECONV, BootScan, MaxChi, Chimaera, SiScan, and 3Seq, were run with default settings in the Recombination Detection Program (RDP) package version 4.0, and were performed on the alignment of FeMV sequences.…”