Molecular characterization of a novel coronavirus associated with epizootic catarrhal enteritis (ECE) in ferrets

AbstractA novel coronavirus, designated as ferret enteric coronavirus (FECV), was identified in feces of domestic ferrets clinically diagnosed with epizootic catarrhal enteritis (ECE). Initially, partial sequences of the polymerase, spike, membrane protein, and nucleocapsid genes were generated using coronavirus consensus PCR assays. Subsequently, the complete sequences of the nucleocapsid gene and the last two open reading frames at the 3′ terminus of the FECV genome were obtained. Phylogenetic analyses based on predicted partial amino acid sequences of the polymerase, spike, and membrane proteins, and full sequence of the nucleocapsid protein showed that FECV is genetically most closely related to group 1 coronaviruses. FECV is more similar to feline coronavirus, porcine transmissible gastroenteritis virus, and canine coronavirus than to porcine epidemic diarrhea virus and human coronavirus 229E. Molecular data presented in this study provide the first genetic evidence for a new coronavirus associated with clinical cases of ECE

Ocular and Neural Distribution of Feline Herpesvirus-1 During Active and Latent Experimental Infection in Cats.

Background Herpes simplex virus 1 (HSV-1) and varicella zoster virus (VZV) cause extensive intra-ocular and neural infections in humans and are closely related to Felid herpes virus 1 (FeHV-1). We report the extent of intra-ocular replication and the extent and morphological aspects of neural replication during the acute and latent phases of FeHV-1 infection. Juvenile, SPF cats were inoculated with FeHV-1. Additional cats were used as negative controls. Cats were euthanized on days 6, 10, and 30 post-inoculation. Results FeHV-1 was isolated from the conjunctiva, cornea, uveal tract, retina, optic nerve, ciliary ganglion (CG), pterygopalatine ganglion (PTPG), trigeminal ganglion (TG), brainstem, visual cortex, cerebellum, and olfactory bulb of infected cats during the acute phase, but not the cranial cervical ganglion (CCG) and optic chiasm. Viral DNA was detected in all tissues during acute infection by a real-time quantitative PCR assay. On day 30, viral DNA was detected in all TG, all CCG, and 2 PTPG. Histologically mild inflammation and ganglion cell loss were noted within the TG during acute, but not latent infection. Using linear regression, a strong correlation existed between clinical score and day 30 viral DNA copy number within the TG. Conclusions The correlation between clinical score and day 30 viral DNA copy number suggests the severity of the acute clinical infection is related to the quantity of latent viral DNA. The histologic response was similar to that seen during HSV-1 or VZV infection. To the author’s knowledge this is the first report of FeHV-1 infection involving intraocular structures and autonomic ganglia

New Hosts for Equine Herpesvirus 9

Equine herpesvirus 9 was detected in a polar bear with progressive encephalitis; the source was traced to 2 members of a potential equid reservoir species, Grevy’s zebras. The virus was also found in an aborted Persian onager. Thus, the natural host range is extended to 6 species in 3 mammalian orders

Novel Calicivirus Identified in Rabbits, Michigan, USA

This virus is distinct from rabbit hemorrhagic disease virus

Sensitivity and specificity of monoclonal and polyclonal immunohistochemical staining for West Nile virus in various organs from American crows (Corvus brachyrhynchos)

<p>Abstract</p> <p>Background</p> <p>Based on results of earlier studies, brain, heart and kidney are most commonly used for West Nile virus (WNV) detection in avian species. Both monoclonal and polyclonal antibodies have been used for the immunohistochemical diagnosis of WNV in these species. Thus far, no studies have been performed to compare the sensitivity and specificity of monoclonal and polyclonal antibodies in detecting WNV in American crows (<it>Corvus brachyrhynchos</it>). Our objectives were to determine 1) the comparative sensitivities of monoclonal and polyclonal antibodies for immunohistochemical (IHC) diagnosis of WNV infection in free-ranging American crows, 2) which organ(s) is/are most suitable for IHC-based diagnosis of WNV, and 3) how real-time RT-PCR on RNA extracted from formalin-fixed paraffin-embedded tissues compared to IHC for the diagnosis of WNV infection.</p> <p>Methods</p> <p>Various combinations, depending on tissue availability, of sections of heart, kidney, brain, liver, lung, spleen, and small intestine from 85 free-ranging American crows were stained using a rabbit-polyclonal anti-WNV antibody as well as a monoclonal antibody directed against an epitope on Domain III of the E protein of WNV. The staining intensity and the extent of staining were determined for each organ using both antibodies. Real-time RT-PCR on formalin-fixed paraffin-embedded tissues from all 85 crows was performed.</p> <p>Results</p> <p>Forty-three crows were IHC-positive in at least one of the examined organs with the polyclonal antibody, and of these, only 31 were positive when IHC was performed with the monoclonal antibody. Real-time RT-PCR amplified WNV-specific sequences from tissue extracts of the same 43 crows that were IHC-positive using the polyclonal antibody. All other 42 crows tested negative for WNV with real-time PCR and IHC staining. Both antibodies had a test specificity of 100% when compared to PCR results. The test sensitivity of monoclonal antibody-based IHC staining was only 72%, compared to 100% when using the polyclonal antibody.</p> <p>Conclusion</p> <p>The most sensitive, readily identified, positively staining organs for IHC are the kidney, liver, lung, spleen, and small intestine. Real-time RT-PCR and IHC staining using a polyclonal antibody on sections of these tissues are highly sensitive diagnostic tests for the detection of WNV in formalin-fixed tissues of American crows.</p

Molecular Characterization of Noroviruses Detected in Diarrheic Stools of Michigan and Wisconsin Dairy Calves: Circulation of Two Distinct Subgroups

Noroviruses have emerged as the leading worldwide cause of acute non-bacterial gastroenteritis in humans. The presence of noroviruses in diarrheic stool samples from calves on Michigan and Wisconsin dairy farms was investigated by RT-PCR. Norovirus-positive samples were found on all eight farms studied in Michigan and on 2 out of 14 farms in Wisconsin. Phylogenetic analyses of partial polymerase and capsid sequences, derived for a subset of these bovine noroviruses, showed that these strains formed a group which is genetically distinct from the human noroviruses, but more closely related to genogroup I than to genogroup II human noroviruses. Examination of 2 full and 10 additional partial capsid (ORF2) sequences of these bovine strains revealed the presence of two genetic subgroups or clusters of bovine noroviruses circulating on Michigan and Wisconsin farms. One subgroup is “Jena-like”, the other “Newbury agent-2-like”

Malignant transformation of canine oral papillomavirus (CPV1)-associated papillomas in dogs: An emerging concern?

Canine oral papillomavirus (CPV1, also known as COPV), the most common cause of non-neoplastic papillomas, has not been shown to cause squamous cell carcinomas (SCC). Furthermore, malignant transformation of benign papillomas to SCC has only been reported in a single group of dogs with severe combined immunodeficiency infected with CPV2. Here, we report a series of 7 dogs with benign CPV1-associated papillomas with histologic evidence of CPV1 causing malignant transformation to carcinoma in situ and ultimately SCC. Expression of p53 and p16 proteins in CPV1-infected cells within the benign papillomas and lesions that progressed into SCC also supported an association between papillomavirus and malignant transformation. Moreover, our retrospective analysis indicated that while there have been increased numbers of viral papillomas with malignant transformation, the number of annually diagnosed canine viral papillomas has remained constant over the past decade in our laboratory. We speculate that either an altered host immunity from increased usage of immunosuppressive drugs or changing environmental factors, e.g. increase exposure to UV radiation, may cause an increased oncogenic potential of this “low-risk” virus. This study aims to raise awareness of the malignant potential of CPV1 and to encourage further investigations into the cause of this suspected change in its oncogenic potential. Keywords: Canine oral papillomavirus, Benign lesions, Malignant transformation, Squamous cell carcinom

Malignant transformation of canine oral papillomavirus (CPV1)-associated papillomas in dogs: An emerging concern?

Canine oral papillomavirus (CPV1, also known as COPV), the most common cause of non-neoplastic papillomas, has not been shown to cause squamous cell carcinomas (SCC). Furthermore, malignant transformation of benign papillomas to SCC has only been reported in a single group of dogs with severe combined immunodeficiency infected with CPV2. Here, we report a series of 7 dogs with benign CPV1-associated papillomas with histologic evidence of CPV1 causing malignant transformation to carcinoma in situ and ultimately SCC. Expression of p53 and p16 proteins in CPV1-infected cells within the benign papillomas and lesions that progressed into SCC also supported an association between papillomavirus and malignant transformation. Moreover, our retrospective analysis indicated that while there have been increased numbers of viral papillomas with malignant transformation, the number of annually diagnosed canine viral papillomas has remained constant over the past decade in our laboratory. We speculate that either an altered host immunity from increased usage of immunosuppressive drugs or changing environmental factors, e.g. increase exposure to UV radiation, may cause an increased oncogenic potential of this "low-risk" virus. This study aims to raise awareness of the malignant potential of CPV1 and to encourage further investigations into the cause of this suspected change in its oncogenic potential