Search

Dogs are known to be susceptible to influenza A viruses, although information on influenza D virus (IDV) is limited. We investigated the seroprevalence of IDV in 426 dogs in the Apulia region of Italy during 2016 and 2023. A total of 14 samples were positive for IDV antibodies, suggesting exposure to IDV in dogs.

Vector-borne pathogens have been increasingly investigated for their impact on dog and cat health and their zoonotic potential. The aim of this study was to investigate the prevalence estimates of selected vector-borne pathogens in client-owned pets from the Giza and Cairo governorates, Egypt.  Out of 200 dogs and 100 cats, 94 (47%) and 23 (23%) were positive for at least one of the tested pathogens (P<0.0001). In particular, 84 (42%) dogs and 3 (3%) cats tested PCR-positive for Bartonella spp. (P<0.0001). A significantly higher prevalence of Bartonella spp. was detected in dogs from the rural areas of the Giza governorate (60/77, 79.2%, P<0.0001) compared to those from Cairo governorate. Bartonella henselae was the dominant species infecting dogs (81/200, 40.5%) followed by Candidatus Bartonella merieuxii (3/200, 1.5%), while B. henselae (2/100, 2%) and B. clarridgeiae were rare in cats. Haemoplasma DNA was detected in 17% (34/200) of dogs and 20% (20/100) of cats with increased risk in dogs from Giza rural areas (21/77, 27.27%, P=0.002) and from both dogs (16/63, 25.40%, P=0.03) and cats (7/14, 50%, P<0.002) with anemia. Candidatus Mycoplasma haematoparvum (30/200, 15%) and Mycoplasma haemocanis (4/200, 2%) in dogs and Candidatus Mycoplasma haemominutum (18/100, 18%) and M. haemofelis (2/100, 2%) in cats were detected. Additionally, 2 dogs were positive for C. burnetii DNA. Coinfections were detected in dogs, with the majority (23/200, 11.5%) including B. henselae and C.M. haematoparvum, followed by Mycoplasma haemocanis and C.M. haematoparvum (2/200, 1%) and B. henselae, CMhp and C. burnetii (2/200, 1%). Haemoplasma infection was high in Egyptian dogs and cats with a high prevalence for zoonotic Bartonella spp. in dogs with anemia, highlighting the need to investigate these agents in the diagnostic algorithm of anemia and to adopt preventive measures to protect both animal and human health., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Severe clinical diseases associated to αCoronavirus (αCoV) infections were recently demonstrated for the first time in humans and a closely related but distinct canine CoV (CCoV) variant was identified in the nasopharyngeal swabs of children with pneumonia hospitalized in Malaysia, in 2017-2018. The complete genome sequence analysis demonstrated that the isolated strain, CCoV-HuPn-2018, was a novel canine-feline-like recombinant virus with a unique nucleoprotein. The occurrence of three human epidemics/pandemic caused by CoVs in the recent years and the detection of CCoV-HuPn-2018, raises questions about the ability of these viruses to overcome species barriers from their reservoirs jumping to humans. Interestingly, in this perspective, it is interesting to consider the report concerning new CCoV strains with a potential dual recombinant origin through partial S-gene exchange with porcine transmissible gastroenteritis virus (TGEV) identified in pups died with acute gastroenteritis in 2009. The significance of the ability of CCoVs to evolve is still unclear, but several questions arisen on the biology of these viruses, focusing important epidemiological outcomes in the field, in terms of both virus evolution and prophylaxis. The new CCoV-Hupn-2018 should lead researchers to pay more attention to the mechanisms of recombination among CoVs, rather than to the onset of variants as a result of mutations, suggesting a continuous monitoring of these viruses and in particular of SARS-CoV-2., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Feline chaphamaparvovirus (FeChPV) is a novel parvovirus, first discovered in a multi-facility feline shelter in Canada in 2019, during an outbreak of acute gastro-enteritis (AGE) in cats, and detected at high prevalence (47.0%) in faecal samples. Whether this finding was anecdotal or similar viruses are common components of feline virome is still unclear. Also, the potential impact of this virus on feline health is uncertain. Herewith, a case-control study was performed to investigate whether this novel parvovirus may play a role as enteric pathogen, screening samples collected from cats with and without AGE signs. Furthermore, we extended the research by testing archival paired oropharyngeal and ocular samples collected from cats with or without upper respiratory tract disease (URTD). FeChPV DNA was detected at high prevalence rate (36.8%, 14/38) in clinical cases, representing the most frequently identified enteric virus, followed by feline panleukopenia parvovirus (23.7%, 9/38), feline coronavirus (5.3%, 2/38), feline kobuvirus (5.3%, 2/38) and noroviruses (5.3%, 2/38). The different prevalence rates of FeChPV between the case and control group were statistically significant, suggesting a possible association of the virus with acute gastro-enteric disease. The virus was also detected at low rate in the respiratory samples of cats with (3.3%, 6/183) or without URTD (4.3%, 6/140), although there was no significant association between FeChPV and URTD. The complete VP encoding gene was determined for five viruses and the nearly full-length genome was reconstructed for three viruses, namely 313R/2019/ITA, 284R/2019/ITA and 49E/2019/ITA. In the NS1-based tree, the Italian strains clustered tightly with the two FeChPV prototypes detected in Canada, within a monophyletic cluster related to but clearly distinct from canine chaphamaparvovirus, currently classified in the species Carnivore chaphamaparvovirus 1 (CaChPV-1)., (© 2021 Wiley-VCH GmbH.)

Canine bufavirus (CBuV) is a protoparvovirus, genetically related to human and non-human primate bufaviruses and distantly related to canine parvovirus type 2 (CPV-2). CBuV was initially identified from young dogs with respiratory signs but subsequent studies revealed that this virus is also a common component of the canine enteric virome. In this survey, by assessing archival and recent collections of dogs faecal samples, CBuV DNA was detected with a higher prevalence rate (8.8%) in animals with enteritis than in control animals (5.0%), although this difference was not statistically significant. The rate of co-infections with other enteric viruses in diarrhoeic dogs was high (84.6%), mostly in association with canine parvovirus CPV-2 (90.1%). The complete ORF2 gene was determined in five samples, and the nearly full-length genome was reconstructed for three strains, 62/2017/ITA, 9AS/2005/ITA and 35/2018/ITA. Upon sequence comparison, the viruses appeared highly conserved in the NS1 (97.2%-97.9% nt and 97.5%-98.1% aa identities). In the complete VP2 coding region, three strains were similar to the prototype viruses (99.7-99.8 nt and 99.6%-99.8% aa) whilst strains 9AS/2005/ITA and 35/2016/ITA were distantly related (87.6%-89.3% nt and 93.9%-95.1% aa identities). Interestingly, genetic diversification occurred downstream conserved regions such as the VP1/VP2 splicing signals and/or the G-rich motif in the N terminus of the VP2, suggesting a potential recombination nature. Upon phylogenetic analysis, the two divergent CBuV strains formed a distinct cluster/genotype., (© 2020 Blackwell Verlag GmbH.)

Canine parvovirus (CPV) is a major enteric pathogen of dogs worldwide that emerged in the late 1970s from a feline parvovirus (FPV)-like ancestral virus. Shortly after its emergence, variant CPVs acquired amino acid (aa) mutations in key capsid residues, associated with biological and/or antigenic changes. This study aimed to identify and analyse CPV variants and their capsid mutations amongst Australian dogs, to gain insights into the evolution of CPV in Australia and to investigate relationships between the disease and vaccination status of dogs from which viruses were detected. CPV VP2 sequences were amplified from 79 faecal samples collected from dogs with parvoviral enteritis at 20 veterinary practices in five Australian states. The median age at diagnosis was 4 months (range 1-96 months). Only 3.7% of dogs with vaccination histories had completed recommended vaccination schedules, while 49% were incompletely vaccinated and 47.2% were unvaccinated. For the first time, CPV-2b has emerged as the dominant antigenic CPV variant circulating in dogs with parvoviral enteritis in Australia, comprising 54.4% of viruses, while CPV-2a and CPV-2 comprised 43.1% and 2.5%, respectively. The antigenic variant CPV-2c was not identified. Analysis of translated VP2 sequences revealed a vast repertoire of amino acid (aa) mutations. Several Australian CPV strains displayed signatures in the VP2 protein typical of Asian CPVs, suggesting possible introduction of CPV strains from Asia, and/or CPV circulation between Asia and Australia. Canine parvoviruses were identified containing aa residues typical of FPV at key capsid (VP2) positions, representing reverse mutations or residual mutations retained from CPV-2 during adaptation from an FPV-like ancestor, suggesting that evolutionary intermediates between CPV-2 and FPV are circulating in the field. Similarly, intermediates between CPV-2a-like viruses and CPV-2 were also identified. These findings help inform a better understanding of the evolution of CPV in dogs., (© 2020 Blackwell Verlag GmbH.)

Canine chaphamaparvovirus (CaChPV) is a newly recognised parvovirus discovered by metagenomic analysis during an outbreak of diarrhoea in dogs in Colorado, USA, in 2017 and more recently detected in diarrhoeic dogs in China. Whether the virus plays a role as canine pathogen and whether it is distributed elsewhere, in other geographical areas, is not known. We performed a case-control study to investigate the possible association of CaChPV with enteritis in dogs. CaChPV DNA was detected both in the stools of diarrhoeic dogs (1.9 %, 3/155) and of healthy animals (1.6 %, 2/120). All the CaChPV-infected dogs with diarrhea were mixed infected with other enteric viruses such as canine parvovirus (formerly CPV-2), canine bufavirus (CBuV) and canine coronavirus (CCoV), whilst none of the asymptomatic CaChPV positive animals resulted co-infected. The nearly full-length genome and the partial capsid protein (VP) gene of three canine strains, Te/36OVUD/19/ITA, Te/37OVUD/19/ITA and Te/70OVUD/19/ITA, were reconstructed. Upon phylogenetic analyses based on the NS1 and VP aa sequences, the Italian CaChPV strains tightly clustered with the American reference viruses. Distinctive residues could be mapped to the deduced variable regions of the VP of canine and feline chaphamaparvoviruses, considered as important markers of host range and pathogenicity for parvoviruses., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Caliciviruses of the Sapovirus genus have been recently detected in dogs. Canine sapoviruses (SaVs) have been identified in the stools of young or juvenile animals with gastro-enteric disease at low prevalence (2.0-2.2%), but whether they may have a role as enteric pathogens and to which extent dogs are exposed to SaVs remains unclear. Here, we report the expression in a baculovirus system of virus like-particles (VLPs) of a canine SaV strain, the prototype virus Bari/4076/2007/ITA. The recombinant antigen was used to develop an enzyme-linked immunosorbent assay (ELISA). By screening an age-stratified collection of serum samples from 516 dogs in Italy, IgG antibodies specific for the canine SaV VLPs were detected in 40.3% (208/516) of the sera. Also, as observed for SaV infection in humans, we observed a positive association between seropositivity and age, with the highest prevalence rates in dogs older than 4 years of age., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A novel protoparvovirus species, related genetically to human bufaviruses, was identified in dogs with respiratory signs. The canine bufavirus was distantly related to the well-known canine protoparvovirus, canine parvovirus type 2, sharing low amino acid identities in the nonstructural protein 1 (40.6%) and in the capsid protein 1 (33.4%). By screening collections of fecal, nasal, and oropharyngeal samples obtained from juvenile dogs (<1 year of age), canine bufavirus DNA appeared as a common component of canine virome. The virus was common in the stool samples of dogs with or without enteric disease and in the nasal and oropharyngeal swab samples of dogs with respiratory signs. However, the virus was not detected in nasal and oropharyngeal swab samples from animals without clinical signs.

By screening a collection of fecal samples from young dogs from different European countries, noroviruses (NoVs) were found in 13/294 (4.4%) animals with signs of enteritis whilst they were not detected in healthy dogs (0/42). An informative portion of the genome (3.4kb at the 3' end) was generated for four NoV strains. In the capsid protein VP1 region, strains 63.15/2015/ITA and FD53/2007/ITA were genetically related to the canine GVI.2 strain C33/Viseu/2007/PRT (97.4-98.6% nt and 90.3-98.6% aa). Strain FD210/2007/ITA displayed the highest identity to the GVI.1 canine strain Bari/91/2007/ITA (88.0% nt and 95.0% aa). Strain 5010/2009/ITA displayed only 66.6-67.6% nt and 75.5-81.6% aa identities to the GVI.1 canine strains FD210/2007/ITA and Bari/91/2007/ITA and the GVI feline strain M49-1/2012/JPN. Identity to the other canine/feline NoVs strains in the VP1 was lower than 67.6% nt and 62.7% aa. Based on the full-length VP1 amino acid sequence and the criteria proposed for distinction of NoV genotypes, the canine NoV 5010/2009/ITA could represent the prototype of a third GVI genotype, thus providing further evidence for the genetic heterogeneity of NoVs in carnivores., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Molecular and serological data suggest that noroviruses (NoVs) might be transmitted between humans and domestic carnivores. In this study we screened an age-stratified collection of canine sera (n=516) by using an ELISA assay based on virus-like particles (VLPs) of human NoVs GII.4 and GIV.1 and carnivore NoVs GIV.2 and GVI.2. Antibodies against GII.4 and GIV.1 human NoVs and GIV.2 and GVI.2 NoVs from carnivores were identified in dog sera (13.0%, 67/516) suggesting their exposure to homologous and heterologous NoVs. Analysis of the trends of age-class prevalence showed a gradual increase in the positive rate from 9.0% and 7.0%, in young dogs <1year of age to 15.0% in dogs older than 12 years, for GII.4 and GVI.2 NoVs, respectively. A significant difference in the IgG distribution by age classes was observed for GIV.1 NoVs, with the highest rate of antibodies (7.0%) in the age group <1year and the lowest (1.0%) in the age-classes 7-9 (P=0.049). High correlation between the reactivity to GII.4 and GVI.2 NoVs was observed, likely due to conserved epitopes in the capsid structure., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In 2003, a novel calicivirus, the vesivirus (VeV) strain 2117, was identified incidentally as a contaminant in Chinese Hamster Ovary (CHO) cell cultures by a German pharmaceutical company. Similar contaminations have been documented in three additional episodes, in bio-reactors used for production of recombinant drugs. More, recently 2117-like VeVs have also been identified at high prevalence in the stools from asymptomatic kennel dogs and only sporadically in diarrhoeic and healthy household dogs. In this study, antibodies for 2117-like viruses were detected in 21.5% of sera from household dogs, indicating that they are common viruses in the canine host., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Splenitis is uncommonly reported in dogs. Herein, the authors describe its prevalence, clinical findings and outcomes, histologic patterns, and causes. Splenic samples of dogs diagnosed with splenitis between 2005 and 2013 were collected and stained with hematoxylin and eosin, Gram, green-Gram, Giemsa, periodic acid-Schiff, and Ziehl-Neelsen. Samples were processed for polymerase chain reaction (PCR) to detect bacteria, fungi, and protozoa ( Leishmania infantum, Hepatozoon canis). Thirty-three of 660 splenic samples (5%) had splenitis. Clinical findings and outcomes were available in 19 dogs (58%); 49% had weakness, 33% had fever, and 84% survived. The most frequent inflammatory patterns included purulent splenitis (27%), pyogranulomatous splenitis (24%), and neutrophilic perisplenitis (15%). One dog had a putative diagnosis of primary splenitis; in 8 dogs, microorganisms were identified histologically or by PCR in the spleen without obvious comorbidities. Twenty-four dogs (73%) had concurrent diseases; a permissive role in the development of splenitis was suspected in 21 of these cases. Histologic examination identified the cause of splenitis in 10 dogs. Bacteria were identified by PCR in 23 cases, but the bacteria were confirmed histologically in only 6 of these. Leishmania was detected with PCR in 6 dogs. Leishmania was identified in 1 dog and H. canis in another histologically, but both were PCR negative. Fungi were identified in 8 spleens by PCR and in 1 by histology. This study suggests that splenitis is uncommon in dogs and is frequently associated with systemic diseases. Prognosis is favorable in most cases. Identification of bacteria, fungi, and protozoa in the spleens of affected dogs with PCR should be interpreted cautiously, because the findings are not confirmed histologically in many cases.

A molecular survey for traditional and emerging pathogens associated with canine infectious respiratory disease (CIRD) was conducted in Italy between 2011 and 2013 on a total of 138 dogs, including 78 early acute clinically ill CIRD animals, 22 non-clinical but exposed to clinically ill CIRD dogs and 38 CIRD convalescent dogs. The results showed that canine parainfluenza virus (CPIV) was the most commonly detected CIRD pathogen, followed by canine respiratory coronavirus (CRCoV), Bordetella bronchiseptica, Mycoplasma cynos, Mycoplasma canis and canine pneumovirus (CnPnV). Some classical CIRD agents, such as canine adenoviruses, canine distemper virus and canid herpesvirus 1, were not detected at all, as were not other emerging respiratory viruses (canine influenza virus, canine hepacivirus) and bacteria (Streptococcus equi subsp. zooepidemicus). Most severe forms of respiratory disease were observed in the presence of CPIV, CRCoV and M. cynos alone or in combination with other pathogens, whereas single CnPnV or M. canis infections were detected in dogs with no or very mild respiratory signs. Interestingly, only the association of M. cynos (alone or in combination with either CRCoV or M. canis) with severe clinical forms was statistically significant. The study, while confirming CPIV as the main responsible for CIRD occurrence, highlights the increasing role of recently discovered viruses, such as CRCoV and CnPnV, for which effective vaccines are not available in the market., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Caliciviruses are important human and animal pathogens. Novel caliciviruses have been identified recently in dogs, raising questions about their pathogenic role and concerns regarding their zoonotic potential. By screening stool samples of young or juvenile dogs using RT-PCR assays, sapoviruses (SaVs) were found in 7/320 (2.2%) samples of animals with acute gastroenteritis while they were not detected in healthy animals (0/119). The sequence of a nearly 3kb portion at the 3' end of the genome, encompassing the RNA-dependent RNA polymerase (RdRp), the capsid region (ORF1) and the ORF2 were determined for three strains. A distinctive genetic feature in canine SaVs was a 4-nucleotide (nt) interval between the ORF1 and ORF2. Two strains (Bari/4076/07/ITA and Bari/253/07/ITA) were very closely related in the RdRp and capsid regions to the strain AN210D/09/USA (90.4-93.9% nt), while strain Bari/5020/07/ITA displayed only 71.0-72.0% nt identity to this group of canine SaVs and 76.0% to strain AN196/09/USA. Overall, these findings indicate that the canine SaVs detected in Italy may represent distinct capsid types, although all currently known SaVs segregate into the novel proposed genogroup, tentatively named as GXIII., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Species C rotaviruses (RVC) have been identified in humans and animals, including pigs, cows and ferrets. In dogs, RVC strains have been reported anecdotally on the basis of visualization of rotavirus-like virions by electron microscopy combined with specific electrophoretic migration patterns of the genomic RNA segments. However, no further molecular characterization of these viruses was performed. Here, we report the detection of a canine RVC in the stool of a dog with enteritis. Analysis of the complete viral genome uncovered distinctive genetic features of the identified RVC strain. The genes encoding VP7, VP4 and VP6 were distantly related to those of other RVC strains and were putatively classified as G10, P8 and I8, respectively. The new strain was named RVC/Dog-wt/HUN/KE174/2012/G10P[8]. Phylogenetic analyses revealed that canine RVC was most closely related to bovine RVC strains with the exception of the NSP4 gene, which clustered together with porcine RVC strains. These findings provide further evidence for the genetic diversity of RVC strains.

Vesiviruses have been detected in several animal species and as accidental contaminants of cells. We detected vesiviruses in asymptomatic kennel dogs (64.8%) and symptomatic (1.1%) and asymptomatic (3.5%) household dogs in Italy. The full-length genome of 1 strain, Bari/212/07/ITA, shared 89%-90% nt identity with vesiviruses previously detected in contaminated cells.

We identified unusual rotavirus strains in fecal specimens from sheltered dogs in Hungary by viral metagenomics. The novel rotavirus species displayed limited genome sequence homology to representatives of the 8 rotavirus species, A-H, and qualifies as a candidate new rotavirus species that we tentatively named Rotavirus I.

A canine Rotavirus A strain was identified in the fecal specimen of a young dog during 2012 in Hungary. The strain RVA/Dog-wt/HUN/135/2012/G3P[3] shared complete genotype constellation (G3-P[3]-I3-R3-C3-M3-A15-N2-T3-E3-H6) and high genome sequence similarity (nt, 98.8 %) with a historic human strain, RVA/Human-tc/ITA/PA260-97/1997/G3P[3]. This study provides evidence for the canine origin of the unusual NSP1 genotype, A15, and reinforces the hypothesis of direct interspecies transmission of canine rotaviruses to humans.

Dog circovirus (DogCV) was identified in an outbreak of enteritis in pups in Italy. The disease was observed in 6 young dachshunds pups of a litter from a breeding kennel and caused the death of 2 dogs. Upon full-genome analysis, the virus detected in one of the dead pups (strain Bari/411-13) was closely related to DogCVs that have been recently isolated in the USA. The present study, if corroborated by further reports, could represent a useful contribution to the knowledge of the pathogenic potential of DogCV and its association with enteritis in dogs.

Canine distemper virus (CDV) is a major pathogen of dogs and represents a serious threat to both unvaccinated and vaccinated animals. This study surveyed dogs with or without clinical signs related to canine distemper from different regions of Brazil from 2008 to 2012. A total of 155 out of 386 animals were found to be CDV positive by RT-PCR; 37 (23.8%) dogs were asymptomatic at the time of sampling, and 90 (58%) displayed clinical signs suggestive of distemper. Nineteen (12.2%) dogs had a record of complete vaccination, 15 (9.6%) had an incomplete vaccination protocol, and 76 (49%) had no vaccination record. Based on the sequence analysis of the complete hemagglutinin gene of 13 samples, 12 of the strains were characterized as Genotype South America-I/Europe. Considering criteria of at least 95% nucleotide identity to define a genotype and 98% to define a subgenotype, South America-I/Europe sequences segregated into eight different phylogenetically well-defined clusters that circulated or co-circulated in distinct geographical areas. Together, these findings highlight the relevance of CDV infection in Brazilian dogs, demonstrate the predominance of one genotype in Brazil and support the need to intensify the current control measures., (Copyright © 2014 Elsevier B.V. All rights reserved.)

An outbreak of canine infectious respiratory disease (CIRD) associated to canine pneumovirus (CnPnV) infection is reported. The outbreak occurred in a shelter of the Apulia region and involved 37 out of 350 dogs that displayed cough and/or nasal discharge with no evidence of fever. The full-genomic characterisation showed that the causative agent (strain Bari/100-12) was closely related to CnPnVs that have been recently isolated in the USA, as well as to murine pneumovirus, which is responsible for respiratory disease in mice. The present study represents a useful contribution to the knowledge of the pathogenic potential of CnPnV and its association with CIRD in dogs. Further studies will elucidate the pathogenicity and epidemiology of this novel pneumovirus, thus addressing the eventual need for specific vaccines.

A catalase-negative MRSA strain and a methicillin resistant Staphylococcus pseudintermedius strain (MRSP) were isolated from a dog affected by a severe form of pododermatitis. The catalase negative isolate was typed as SCCmec I, PVL negative, ST5 t002 strain. A deletion at position 487 of the kat gene altered the functionality of the catalase enzyme. This is the first report of a catalase-negative MRSA in animals. As catalase test is a rapid assay routinely employed for the identification of staphylococci in clinical microbiology laboratories, the presence of MRSA with this uncommon phenotype may be underestimated. Moreover, catalase-negative staphylococci should be investigated more in-depth in order to assess their virulence., (Copyright © 2013 Elsevier B.V. All rights reserved.)

An epidemiological survey for canine parvovirus (CPV) was conducted by collecting 615 faecal samples from dogs with diarrhoea in different European countries. Molecular methods showed that CPV-2a was predominant in most countries, followed by CPV-2c and CPV-2b, whereas 30 strains were not characterised. By sequence analysis of the full-length VP2 gene, 20 of these viruses were characterised as CPV-2c mutants having the synonymous mutation A4061G in the probe-binding region that prevented correct strain characterisation. A real-time polymerase chain reaction (PCR) assay using a minor groove binder probe was able to recognise both mutant and classical CPV-2c strains. These results indicate that the emergence of CPVs with mutations affecting the oligonucleotide-binding region needs a continuous update of molecular diagnostic tools in order to detect efficiently those emerging strains., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Highly virulent pantropic canine coronavirus (CCoV) strains belonging to subtype IIa were recently identified in dogs. To assess the distribution of such strains in Europe, tissue samples were collected from 354 dogs that had died after displaying systemic disease in France (n = 92), Hungary (n = 75), Italy (n = 69), Greece (n = 87), The Netherlands (n = 27), Belgium (n = 4), and Bulgaria (n = 1). A total of 124 animals tested positive for CCoV, with 33 of them displaying the virus in extraintestinal tissues. Twenty-four CCoV strains (19.35% of the CCoV-positive dogs) detected in internal organs were characterized as subtype IIa and consequently assumed to be pantropic CCoVs. Sequence and phylogenetic analyses of the 5' end of the spike protein gene showed that pantropic CCoV strains are closely related to each other, with the exception of two divergent French viruses that clustered with enteric strains.

The molecular characterization of a strain of Canine minute virus (CnMV) associated with neonatal death is reported. Three newborn puppies of a litter of Jack Russell terrier dogs died after displaying systemic disease, whereas 2 surviving puppies showed no clinical signs with the exception of transient cardiac abnormalities that were evident by electrocardiography. Necropsy of 1 dead puppy revealed severe lesions in the internal organs. A strain of Canine minute virus was detected in tissue samples collected from the puppy, and virus circulation was demonstrated by molecular or serological testing in the dam, puppies of the same litter, and other puppies in the same kennel. By sequence and phylogenetic analysis of the gene encoding for the VP2 capsid protein, the strain circulating in the kennel was found to be related to recent Asian CnMV isolates. Continuous molecular surveillance for CnMV in kennels, shelters, and rescue centers would expand the knowledge base on the epidemiological and pathogenetic features of CnMV, which has been known for several decades but still poorly understood.

Infection by a novel canine astrovirus was associated with gastroenteritis in two dogs. The virus displayed 70.3 to 73.9% amino acid identity to other canine astroviruses in the full-length capsid. Specific antibodies were detected in the convalescent-phase sera of the dogs, indicating seroconversion. Also, the virus appeared weakly related antigenically to the prototype canine astrovirus isolate ITA/2008/Bari.

Noroviruses are recognized as emerging enteric pathogens of humans and have been identified in recent years in a number of mammalian species. The role of noroviruses as pathogens in immune-competent animals and under natural conditions remains uncertain, although both homologous and heterologous animal models are now available to investigate the pathogenesis, the immune response, and the molecular mechanism regulating norovirus infection. Recently, evidence has been gathered that noroviruses may also circulate in domestic carnivores. The zoonotic implications of these novel viruses deserve more attention, due to the strict social interactions between humans and pets.

Canine astroviruses appear to be widespread geographically. The prevalence may be significantly higher in pups with gastroenteric disease than in asymptomatic animals and virus shedding has been shown to correlate with gastroenteric signs in naturally infected dogs. Animal experiments are required to understand better the pathogenic role of astroviruses in dogs.

Astroviruses (AstVs) have been identified only occasionally in dogs. A canine AstV, strain Bari/08/ITA, was detected from a pup with gastroenteric signs and the virus was isolated in cell culture and characterized molecularly. In the full-length capsid protein, the virus displayed genetic similarities (83.5 % aa identity) to another canine AstV strain, although a high rate of variation occurred in the hypervariable domain, which is related to AstV antigenic specificity. Specific antibodies were detected in the convalescent dog, indicating seroconversion, and in 59 % of a collection of dog serum samples. Using primers specific for canine AstV, designed to detect a conserved region of ORF1b, canine AstVs were detected in 24.5 % of young pups with gastroenteritis, either alone or in mixed infections with other canine pathogens. In contrast, AstVs were detected in only 9.3 % of asymptomatic pups. These findings indicate that canine AstVs are common in dogs and may suggest a possible role as canine enteric pathogens.

RNA-RNA hybridization assays and complete genome sequence analyses have shown that feline rotavirus (FRV) and canine rotavirus (CRV) strains display at least two distinct genotype constellations (genogroups), represented by the FRV strain RVA/Cat-tc/AUS/Cat97/1984/G3P[3] and the human rotavirus (HRV) strain RVA/Human-tc/JPN/AU-1/1982/G3P3[9], respectively. G3P[3] and G3P[9] strains have been detected sporadically in humans. The complete genomes of two CRV strains (RVA/Dog-tc/ITA/RV198-95/1995/G3P[3] and RVA/Dog-tc/ITA/RV52-96/1996/G3P[3]) and an unusual HRV strain (RVA/Human-tc/ITA/PA260-97/1997/G3P[3]) were determined to further elucidate the complex relationships among FRV, CRV and HRV strains. The CRV strains RV198-95 and RV52-96 were shown to possess a Cat97-like genotype constellation. However, 3 and 5 genes of RV198-95 and RV52-96, respectively, were found in distinct subclusters of the same genotypes, suggesting the occurrence of reassortment events among strains belonging to this FRV/CRV/HRV genogroup. Detailed phylogenetic analyses of the HRV strain PA260-97 showed that (i) 8 genome segments (VP3, VP4, VP6, VP7 and NSP2-5) clustered closely with RV198-95 and/or RV52-96; (ii) 2 genome segments (VP1 and VP2) were more closely related to HRV AU-1; and (iii) 1 genome segment (NSP1) was distantly related to any other established NSP1 genotypes and was ratified as a new NSP1 genotype, A15. These findings suggest that the human strain PA260-97 has a history of zoonotic transmission and is likely a reassortant among FRV/CRV strains from the Cat97 and AU-1-like genogroups. In addition, a potential third BA222-05-like genogroup of FRV and HRV strains should be recognized, consisting of rotavirus strains with a stable genetic genotype constellation of genes also partially related to bovine rotavirus (BRV) and bovine-like rotaviruses. The detailed phylogenetic analysis indicated that three major genotype constellations exist among FRV, CRV and feline/canine-like HRV strains, and that reassortment and interspecies transmission events contribute significantly to their wide genetic diversity., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Recently, canine coronavirus (CCoV) strains with putative recombinant origin with porcine transmissible gastroenteritis virus (TGEV) were shown to be widespread in Europe. In this study, a killed vaccine against TGEV-like CCoV strains, included in the new subtype CCoV-IIb, was developed through inactivation with betapropiolactone and emulsification with MF59™ adjuvant. Safety, immunogenicity and efficacy of the developed vaccine were evaluated in vivo. Five 10-week-old beagle pups were administered (three weeks apart) two vaccine doses, whereas two animals served as unvaccinated controls. The vaccine was shown to be safe as no local neither systemic reactions were observed after first and second dose administration. Serum antibodies against CCoV were detected in vaccinates starting from study day 14 (by enzyme-linked immunosorbent assay) or 28 (by virus neutralisation test). Subsequent challenge with virulent CCoV-IIb resulted in the development of mild gastroenteric disease in control pups, whereas vaccinates did not display clinical signs. Faecal shedding of the challenge virus occurred in both treatment groups, but vaccinated dogs were found to shed very low viral titres in comparison to controls. The developed vaccine may help control the CCoV-IIb-induced disease (and active virus circulation) in environments, such as kennels and shelters, where the pathogenic potential of this virus is greater as a consequence of predisposing factors and concurrent infections., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Canine parvovirus (CPV) and canine coronavirus (CCoV) are considered the main pathogens responsible for acute gastroenteritis in dogs. From a collection of 250 samples, seven CPV strains and three CCoV strains were identified in symptomatic Irish dogs. Samples were screened for the viruses using polymerase chain reaction (PCR) and typed via DNA sequence analysis. Three CPV strains were characterized as CPV-2a, while four others were characterized as CPV-2b. To date, CPV-2c remains unreported in Ireland. Two CCoV strains were characterized as CCoV-II and one as CCoV-I. In the case of one sample, PH4/09/Ire, a mixed infection with CPV and CCoV was detected.

An epidemiological survey for canine parvovirus (CPV) and canine coronavirus (CCoV) infections was conducted in Western Europe. A total of 156 faecal samples were collected from dogs with diarrhoea in Spain (n=47), Italy (n=39), France (n=26), Germany (n=21), the United Kingdom (n=8), Belgium (n=10), and the Netherlands (n=5). Using molecular assays for virus detection and characterisation, CPV and CCoV were found to be widespread in European dog populations, either alone or in mixed infections. In agreement with previous reports, the original type CPV-2 was shown not to circulate in European dogs. The recently identified virus variant CPV-2c was predominant in Italy and Germany and present at high rates in Spain and France but was not detected in the UK or Belgium. Except for the UK, CCoV genotype I was identified in all European countries involved in the survey, albeit at a lower prevalence rates than CCoV genotype II., (Copyright © 2009 Elsevier Ltd. All rights reserved.)

A TaqMan-based real-time PCR assay targeting the glycoprotein B-encoding gene was developed for diagnosis of canid herpesvirus 1 (CHV-1) infection. The established assay was highly specific, since no cross-reactions were observed with other canine DNA viruses, including canine parvovirus type 2, canine minute virus, or canine adenovirus types 1 and 2. The detection limit was 10(1) and 1.20 x 10(1) DNA copies per 10 microl(-1) of template for standard DNA and a CHV-1-positive kidney sample, respectively: about 1-log higher than a gel-based PCR assay targeting the thymidine kinase gene. The assay was also reproducible, as shown by satisfactory low intra-assay and inter-assay coefficients of variation. CHV-1 isolates of different geographical origins were recognised by the TaqMan assay. Tissues and clinical samples collected from three pups which died of CHV-1 neonatal infection were also tested, displaying a wide distribution of CHV-l DNA in their organs. Unlike other CHV-1-specific diagnostic methods, this quantitative assay permits simultaneous detection and quantitation of CHV-1 DNA in a wide range of canine tissues and body fluids, thus providing a useful tool for confirmation of a clinical diagnosis, for the study of viral pathogenesis and for evaluation of the efficacy of vaccines and antiviral drugs., (Copyright (c) 2010 Elsevier B.V. All rights reserved.)

Brucella spp. is a worldwide zoonotic pathogen. Infection by Brucella canis in dogs is endemic in the Southern USA and in Central and South America, but it appears sporadically in other parts of the world, including Europe. Tissue samples from a dog with chronic prostatitis, discospondylitis and locomotor problems were subjected to clinical and laboratory examinations. B. canis was detected by PCR in biological fluids and tissues of the animal, while antibodies to B. canis were found in the serum, providing additional strong evidence for the circulation of B. canis in Italy.

An outbreak of norovirus (NoV) infection was identified in a kennel. Sequence analysis of a short fragment in the polymerase complex indicated the clonal origin of the strains, which were similar to the prototype canine NoV strain GIV.2/Bari/170/07-4/ITA (94.7% nucleotide identity). The findings demonstrate that canine NoV circulates in dogs in Greece and that it can spread easily across a group of animals.

Recombinant canine coronaviruses, resembling the transmissible gastroenteritis virus of swine (TGEV) in a 5' fragment of the S glycoprotein, have been detected recently and showed to be present in canine populations. The 5' fragment of the S protein (S') of a TGEV-like canine coronavirus (CCoV), strain 174/06, was expressed in an Escherichia coli cell-free system. The purified recombinant polypeptide was employed to develop an ELISA test for the detection of TGEV-like CCoV-specific antibodies in dog sera. Four canine sera positive for TGEV-like CCoV, six sera positive to classical CCoV-II strains and 10 negative control sera were examined. The recombinant S' was not recognized by antibodies to classical CCoV-II, as only sera from dogs infected experimentally with TGEV-like CCoV reacted strongly with the recombinant S' polypeptide whereas dog sera with antibodies to classical CCoV-II did not react. As classical CCoV-II and TEGV-like CCoVs are related antigenically, the recombinant S' ELISA is a useful method to investigate serologically the prevalence of TGEV-like CCoVs in dogs., (2009 Elsevier B.V. All rights reserved.)

Recently, an outbreak of fatal infection caused by a pantropic variant (strain CB/05) of canine coronavirus (CCoV) has been reported. In this study, evidence is provided that immunity induced by natural exposure to enteric CCoV is not fully protective against strain CB/05. Twenty-two, 10-week-old beagles with a recent natural infection by enteric CCoV were randomly distributed in two experimental groups of eight (groups A and B) and one control group of six (group C) dogs. Dogs in groups A and B were inoculated oronasally with different doses (4 x 10(5) or 4 x 10(3)TCID(50)) of the pantropic strain CB/05, whereas dogs in group C were used as negative controls. Clinical, post-mortem and virological investigations showed that, despite the high serum antibody titres induced by the prior natural infection with enteric CCoV, dogs were susceptible to experimental infection with strain CB/05. This was shown by the occurrence of faecal shedding, and dogs displaying moderate clinical signs, mainly vomiting and diarrhoea. Involvement of the lymphoid tissues was evident as demonstrated by the acute lymphopenia (below 70% of the initial counts), gross lesions in spleen and lymph nodes and detection of CB/05 RNA in thymus, spleen and lymph nodes of some infected dogs. The presence of viral RNA in lymphoid tissues was observed only in dogs euthanised in the early stages of infection and the clinical course of the infection was unrelated to the viral dose administered. The present study demonstrates that strain CB/05 is able to induce infection and disease in dogs seropositive to enteric CCoV, thus highlighting the need for extensive epidemiological investigation and for the possible development of novel antigenically relevant vaccines.

Coronaviruses of potential recombinant origin with porcine transmissible gastroenteritis virus (TGEV), referred to as a new subtype (IIb) of canine coronavirus (CCoV), were recently identified in dogs in Europe. To assess the distribution of the TGEV-like CCoV subtype, during 2001-2008 we tested fecal samples from dogs with gastroenteritis. Of 1,172 samples, 493 (42.06%) were positive for CCoV. CCoV-II was found in 218 samples, and CCoV-I and CCoV-II genotypes were found in 182. Approximately 20% of the samples with CCoV-II had the TGEV-like subtype; detection rates varied according to geographic origin. The highest and lowest rates of prevalence for CCoV-II infection were found in samples from Hungary and Greece (96.87% and 3.45%, respectively). Sequence and phylogenetic analyses showed that the CCoV-IIb strains were related to prototype TGEV-like strains in the 5' and the 3' ends of the spike protein gene.

Coronaviruses (CoVs) are positive-stranded, non-segmented RNA viruses generally responsible for the emergence of respiratory and enteric disease in humans, companion animals and livestock. Their aptitude to evolve by genetic recombination and/or point mutation is recognized, thus giving rise to new viral genotypes and mutants with different tissues or host tropism. In particular, a probable origin from the strictly related bovine coronavirus (BCoV) or, alternatively, from a common ancestor has been suggested for some group 2a CoVs, including canine respiratory coronavirus (CRCoV). In this study, we report the sequence analysis of the viral RNA 3'-end of an Italian CRCoV, strain 240/05, together with the sequence comparison with extant bovine-like viruses including the sole CRCoV strain 4182 previously described. Interestingly, although the structural proteins show the same features of CRCoV 4182, the genomic region between the spike and the envelope protein genes of CRCoV 240/05 encodes for three distinct products, including the equivalent bovine 4.9 kDa non-structural protein and a truncated form of the 4.8 kDa protein, whereas CRCoV 4182 has a unique 8.8 kDa protein.

The sequence of the full-length gene encoding for the main capsid protein VP2 of 58 canine parvovirus (CPV) type 2c strains, along with recent CPV-2a/2b strains, was determined and analysed in comparison with reference CPV isolates. The CPV-2c strains displayed a low genetic variability and shared amino acid changes already detected in recent CPV-2a/2b isolates, with a phylogenetic clustering accounting for their geographical distribution. Analysis of the selection pressure driving CPV evolution confirmed that the VP2 gene is under purifying selection. The emergence and global spread of the new CPV variant provides an interesting model to better understand virus evolution.

Four canine coronavirus type II (CCoV-II) strains were identified in the guts and internal organs of pups which had died of acute gastroenteritis. The CCoV-II strains were strictly related to porcine transmissible gastroenteritis virus (TGEV) in the N-terminal domain of the spike protein, whereas in the other parts of the genome, a higher genetic relatedness to recent CCoV-II isolates was observed. Experimental infection of dogs with a TGEV-like isolate induced mild gastroenteritis without any systemic involvement. By virus neutralization tests, antigenic differences between reference and TGEV-like CCoVs were found. Our data support the potential recombinant origin of the TGEV-like CCoVs.

We identified a novel calicivirus in a pup with enteritis. The isolate was related genetically (90.1% aa identity in the capsid protein) to a lion norovirus strain.

Canine adenoviruses (CAVs) and canine herpesvirus (CHV) are pathogens of dogs that have been known for several decades. The two distinct types of CAVs, type 1 and type 2, are responsible for infectious canine hepatitis and infectious tracheobronchitis, respectively. In the present article, the currently available literature on CAVs and CHV is reviewed, providing a meaningful update on the epidemiologic, pathogenetic, clinical, diagnostic, and prophylactic aspects of the infections caused by these important pathogens.

A pantropic canine coronavirus (CCoV) strain (CB/05) has been recently associated to a fatal outbreak of systemic disease in young dogs. We report the clinical, virological and serological findings in dogs experimentally infected with strain CB/05. The dogs, three 2.5-month-old and two 6-month-old pups, were successfully infected, shedding viral RNA with their faeces for the entire observation period (21 days) and displaying systemic clinical signs resembling those observed during the course of natural infection. Leucopenia (acute lymphopenia) occurred in all infected dogs, with values dropping below 60% of the initial counts. Considering the severity of the CB/05-induced disease, two of the youngest pups were euthanized for ethical reasons at days 8-9 postinfection, whereas the other pups underwent a slow but progressive improvement of their clinical status with complete recovery. At postmortem examination, remarkable lesions were observed in the internal organs of the euthanized pups, that tested positive for CCoV by real-time RT-PCR and virus isolation on cell cultures. All pups seroconverted for CCoV, as shown by the high optical density values and antibody titres detected by ELISA and virusneutralisation tests, respectively. The present study confirms that strain CB/05 is highly pathogenic for dogs, being able to induce a severe disease (and in some cases the death) even in experimental conditions.

The antigenic relationships among the original canine parvovirus type 2 (CPV-2) and the variants CPV-2a, -2b, and -2c were evaluated. Cross-antigenic evaluation revealed clear differences among the CPV variants, which were more appreciable by serum neutralization (SN) than by hemagglutination inhibition. Antigenic differences were found mostly between the original CPV-2 and the variants, but they were also observed among the variants CPV-2a, -2b, and -2c. The variant CPV-2c exhibited a unique antigenic pattern, since it was poorly recognized by the sera of animals immunized with CPV-2, CPV-2a, and CPV-2b. However, animals immunized with CPV-2c exhibited higher SN titers to CPV-2b than to the homologous virus CPV-2c. The observed antigenic differences might drive selection of CPV strains by generating differential immune pressure in the canine population, which raises concerns about vaccine efficacy.

An outbreak of canine parvovirus type 2c (CPV-2c) infection in vaccinated adult dogs is reported. The disease occurred in a breeding kennel in Italy and affected 11 dogs aged between 6 months and 2.5 years, that had been repeatedly administered vaccines containing a type 2 (old type) CPV strain. CPV infection was demonstrated in all diseased dogs by an immunochromatographic test. A CPV strain was isolated from the intestinal content of a 20-month-old pregnant Bernese mountain bitch that underwent a fatal outcome. The strain was characterised as CPV-2c by means of real-time PCR assays using minor groove binder probes. The present report provides further concerns about the real efficacy of type 2-based vaccines against the antigenic variants of CPV and stresses the need for developing new vaccines prepared with the variants currently circulating in the dog population.

A TaqMan real-time RT-PCR assay was developed for detection of RNA transcripts produced by replicating CPV-2. A pair of primers and a TaqMan probe targeting the spliced NS2 mRNA were designed. A synthetic DNA fragment was constructed to mimic the spliced NS2 mRNA by PCR-based gene assembly and was used for generation of standard RNAs. The detection limit of the assay was 1x10(2) RNA copies and standard curve displayed a linear range from 1x10(2) to 1x10(9) copies and a good reproducibility. The assay was then applied to determine the mRNA loads in the tissues of dogs naturally infected by CPV-2. mRNA was detected in a variety of tissues, including the central nervous system.