Chiara Ceci

Canine kobuviruses in diarrhoeic dogs in Italy

Abstract 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.

Detection of hepatitis E virus in slaughtered pigs in Italy

The stools of slaughtered pigs were screened for hepatitis E virus (HEV). HEV RNA was detected in 7.3% of the samples. HEV strains were characterized as genotype 3 subtype c, a cluster previously not described in Italy. These findings provide evidence that slaughterhouse workers may be exposed to HEV infection.

Molecular detection of porcine kobuviruses in Italian swine.

In this study, fecal specimens (n=260) collected from Italian healthy pigs aged between 6 and 10 months were screened by RT-PCR using generic kobuvirus primers. Porcine kobuviruses (PKVs) were detected in 3.85% of the samples tested. Based on the analysis of the partial 3D gene, the Italian sequences identified here were more closely related to PKVs previously identified in Japan, Thailand, Korea, China and Brazil than to the European PKVs recently detected in Hungary and in the Netherlands.

Seroprevalence of Norovirus Genogroup IV Antibodies among Humans, Italy, 2010-2011

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

Characterization of a strain of feline calicivirus isolated from a dog faecal sample.

Abstract To expand the epidemiological understanding of feline calicivirus (FCV) in dogs, genotypic and phenotypic characterizations of a FCV strain isolated from a puppy showing enteritis were performed. After isolation in cell culture, the novel isolate was analysed by RT-PCR and the amplicons obtained were sequenced. In order to characterize the growth properties of the isolate, the size of the plaques, the temperature of inactivation and the kinetics of growth were evaluated. Moreover, the novel strain was used to perform a serological study on 86 canine serum samples and 81 feline sera by virus-neutralization assay. The comparative analysis of nucleotide and amino acid sequences of the isolate, named FCV-Te/10/07, revealed the highest identity to strain FCV-F65. The growth kinetic revealed that strain Te/10/07 grew more rapidly than F9 strain. By virus-neutralization assay, dogs from the same region of the isolate showed antibodies against the FCV-F9 vaccinal strain in 63.9% (55/86) of sera, while antibodies against the Te/10/07 were found in seven sera (8.13%). In cats neutralizing antibodies against Te/10/07 strain were recovered in 50.62% (41/81) of samples tested, even if 38 sera were positives for F9 strain with similar titres or higher. In three cats neutralization to Te/10/07 alone was seen. Our results confirmed the interspecific circulation of FCV strains among different animal species, but new investigations are needed to establish whether FCV is pathogenic in the dog and the role of interspecies circulation in pathogen spreading.

Bovine noroviruses: A missing component of calf diarrhoea diagnosis.

Abstract 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.

In vitro inactivation of feline calicivirus (FCV) by chemical disinfectants: resistance variation among field strains

Several commercial products commonly used for disinfection against feline calicivirus (FCV) have been validated using the vaccine strain F9. However, little information is available regarding the resistance of field strains of FCV to chemical inactivation. In this study, disinfection experiments were performed either on two laboratory-adapted strains or on seven field isolates using three alcohol mixtures and one containing a chlorine compound. For each biocide tested, considerable variability was found among the strains in their susceptibility to inactivation, demonstrating that the effectiveness of disinfection depends not only on the type of chemical compound and exposure time, but also on the FCV strain.

Seroprevalence of St-Valerien-like caliciviruses in Italian swine.

St-Valérien-like viruses are newly recognized porcine caliciviruses recently detected in North America and Europe. In this study, baculovirus-expressed virus-like particles of the St-Valérien strain 25A/ITA were generated and used for the development of an antibody-detection ELISA kit to assess the seroprevalence of these novel caliciviruses in swine. Antibodies specific for St-Valérien-like virus were detected in 63 (10.3 %) of 614 serum samples tested with titres ranging from 1 : 50 (28.6 %) to 1 : 800 (40.7 %). These results indicate that St-Valérien-like infections are common among domestic pigs, italy.