Circoviruses are relatively novel pathogens with increased importance in canids. In this study, we first screened the presence of dog circovirus (DogCV) by molecular methods from a total number of 389 internal organ samples originating from 277 individuals of domestic dogs and wild animals including wolves, foxes and badgers. All the animals originated from Central-Southern Italy, specifically from Abruzzi and Molise regions, areas hosting several natural parks. DogCV was detected in 9/34 wolves (P=26.4%; IC 95%: 14.6-43.1%), 8/209 dogs (P=3.8%; IC 95%: 1.9-7.3%), 0/24 foxes (P=0%; IC 95%: 0-13.8%), 1/10 badgers (P=10%; IC 95%: 1.79-40.4%). However, all DogCV positive animals were shown to be infected at least by an additional key pathogen, including canine distemper virus (CDV) and canine parvovirus type 2. All wolves, but one, presenting DogCV in the internal tissues suffered from CDV infection. The DNA purified from 17 DogCV infected organs was used for whole genome sequencing and phylogenetic analysis.

Canine kobuviruses (CaKVs) are newly recognized picornaviruses recently detected in dogs in the US. By molecular analysis of the whole genome, CaKV that appeared genetically closest to the murine kobuvirus (MuKV) and to the human Aichi virus (AiV), may be classified in the Kobuvirus genus as new genotype (CaKV type 1) within the species Aichivirus A. To date, there are no information on the epidemiology of these novel viruses in other continents. In this study, by screening a collection of 256 dog fecal samples either from diarrhoeic or asymptomatic animals, CaKV was identified in six specimens with an overall prevalence of 2.34% (6/256). All the positive dogs presented diarrhea and were found to be infected by CaKV alone or in mixed infections with canine coronavirus (CCoV) and/or canine parvovirus type 2 (CPV-2). By molecular analysis of the partial 3D gene, all the strains detected displayed a close relatedness with the CaKVs recently identified in the US. This study provides evidence that CaKVs circulate in diarrhoeic dogs in Italy and are not geographically restricted to the North American continent, where they were first signaled.

Antibodies specific to genogroup IV identified in human specimens suggest zoonotic exposure.

Red foxes (Vulpes vulpes) are susceptible to viral diseases of domestic carnivores. In this study, by screening rectal swabs collected from 34 red foxes in Italy, we identified kobuvirus RNA in five samples. Based on analysis of partial RdRp and full-length VP1 genes, all of the strains shared the highest identity with canine kobuviruses (CaKVs) recently detected in the US, the UK and Italy. These findings provide the first evidence of the circulation of these novel viruses in foxes.

Noroviruses are RNA viruses that belong to the Genus Norovirus, Family Caliciviridae, and infect human beings and several animal species, including cattle. Bovine norovirus infections have been detected in cattle of a range of different ages throughout the world. Currently there is no suitable cell culture system for these viruses and information on their pathogenesis is limited. Molecular and serological tests have been developed, but are complicated by the high genetic and antigenic diversity of bovine noroviruses. Bovine noroviruses can be detected frequently in faecal samples of diarrhoeic calves, either alone or in association with other common enteric pathogens, suggesting a role for these viruses in the aetiology of calf enteritis.