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Background: Feline herpesvirus type 1 (FHV-1) is a life threatening highly contagious virus in cats and typically causes upper respiratory tract infections as well as conjunctival and corneal ulcers. Genetic variability could alter the severity of diseases and clinical signs. Despite regular vaccine practices against FHV-1 in China, new FHV-1 cases still commonly occur. The genetic and phylogenetic characteristics of FHV-1 in Kunshan city of China has not been studied yet. Therefore, this study was planned to investigate the prevalence, molecular characteristics of circulating strains, and phylogenetic analyses of FHV-1. This is the first report of molecular epidemiology and phylogenetic characteristics of FHV-1 from naturally infected cats in Kunshan, China., Methods: The occulo-nasal swabs were collected from diseased cats showing respiratory distress, conjunctivitis, and corneal ulcers at different veterinary clinics in Kunshan from 2022 to 2023. Clinical data and general information were recorded. Swab samples were processed for preliminary detection of FHV-1. Thymidine kinase (TK), glycoprotein B (gB) and glycoprotein D (gD) genes were sequenced and analyzed to investigate genetic diversity and evolution of FHV-1., Results: The FHV-1 genome was detected in 43 (43/200, 21.5%) samples using RT-PCR targeting the TK gene. Statistical analysis showed a significant correlation between age, vaccination status and living environment (p < 0.05) with FHV-1 positivity, while a non-significant correlation was observed for FHV-1 positivity and sex of cats (p > 0.05). Additionally, eight FHV-1 positive cats were co-infected with feline calicivirus (8/43,18.6%). FHV-1 identified in the present study was confirmed as FHV-1 based on phylogenetic analyses. The sequence analyses revealed that 43 FHV-1 strains identified in the present study did not differ much with reference strains within China and worldwide. A nucleotide homology of 99-100% was determined among gB, TK and gD genes nucleotide sequences when compared with standard strain C-27 and vaccine strains. Amino acid analysis showed some amino acid substitutions in TK, gB and gD protein sequences. A potential N-linked glycosylation site was observed in all TK protein sequences. Phylogenetic analyses revealed minor variations and short evolutionary distance among FHV-1 strains detected in this study., Conclusions: Our findings indicate that genomes of 43 FHV-1 strains are highly homogenous and antigenically similar, and the degree of variation in major envelope proteins between strains is low. This study demonstrated some useful data about prevalence, genetic characteristics, and evolution of FHV-1 in Kunshan, which may aid in future vaccine development., (© 2024. The Author(s).)

A herd of seven captive-born Grevy's zebras ( Equus grevyi ) experienced an outbreak of nasal discharge and sneezing. Clinical signs, including lethargy and anorexia, were severe and acute in three animals, including a 16-mo-old male that died within 48 h. Treatment of two severely affected zebras included valacyclovir (40 mg/kg PO), meloxicam (0.6 mg/kg IM/PO), and cefquinome (2.5 mg/kg IM q48h). An adult female improved rapidly, and clinical signs resolved within 48 h of treatment. Administration of valacyclovir pellets was very complicated in a 2-mo-old female, and death occurred within 48 h. Histologic examination of the two individuals that died revealed severe fibrinonecrotic interstitial pneumonia with prominent hyaline membranes and type II pneumocyte hyperplasia. Additionally, the 16-mo-old male presented systemic endothelial activation with vascular thrombosis and necrosis and mild nonsuppurative meningoencephalitis. Herpesviral DNA was detected in the lungs of both individuals by nested polymerase chain reaction. The nucleic acid sequence of the amplicons showed 100% similarity with previously published equid alphaherpesvirus 9 sequences. Three additional animals developed mild nasal discharge only and recovered spontaneously. The zebras shared housing facilities with other species, including white rhinoceros ( Ceratotherium simum ), reticulated giraffe ( Giraffa camelopardalis reticulata ), and several antelope species. None of these animals showed clinical signs. Additionally, nasal swabs and whole blood samples were collected from cohoused white rhinoceroses ( n = 3) and springboks ( Antidorcas marsupialis , n = 3) as well as nasal swabs from cohoused reticulated giraffes ( n = 4). Nucleic acid sequence from equid herpesviruses was not detected in any of these samples. The source of the infection in the zebras remains unclear.

Caprine herpesvirus 1 (CpHV-1) is a member of the alpha subfamily of herpersviruses, and is responsible for genital lesions and latent infections in goat population worldwide. Here, we describe goats suffered severe respiratory diseases caused by alphaherpesvirus during 2013 to 2014 in Jiangsu province of China. CpHV-1 was detected out by PCR with a prevalence of 21.1% (40/190), among which three novel CpHV-1 strains were firstly identified and isolated in China. Phylogenetic analysis of glycoprotein B (gB) gene revealed that these new viruses were closely clustered with CpHV-1 strain E/CH. The isolate JSHA1405 was further studied by transmission electron microscopy, and displayed typical herpesvirus morphology. Then, for the first time, complete viral genome of JSHA1405 was sequenced by Illumina Hiseq and third-generation sequencing technology. The viral genome is 134,617 bp in length and the genome characteristics were deeply analyzed. 69 open reading frames were predicted and annotated, which was less than that of BoHV-1. Phylogenetic analysis of the complete genome revealed that JSHA1405 was classified into the same branch with previous CpHV-1 strains as well. Moreover, the pathogenicity test is further evidence that JSHA1405 strain induced obvious symptoms of high fever and nasal discharge in infected goats, consistent with clinical manifestations. This is the first report about isolation and identification of CpHV-1 in China and the first characterization of CpHV-1 genome structure. The research also provides a basis for understanding the characteristics, viral genome and pathogenicity of the virus., Competing Interests: Declaration of Competing Interest None., (Copyright © 2019. Published by Elsevier B.V.)

Feline herpesvirus type 1 (FHV-1) is a widespread cause of respiratory and ocular disease in domestic cats. A spectrum of disease severity is observed in host animals, but there has been limited prior investigation into viral genome factors which could be responsible. Stocks of FHV-1 were established from oropharyngeal swabs obtained from twenty-five cats with signs of infection housed in eight animal shelters around the USA. A standardized numerical host clinical disease severity scoring scheme was used for each cat from which an isolate was obtained. Illumina MiSeq was used to sequence the genome of each isolate. Genomic homogeneity among isolates was relatively high. A general linear model for fixed effects determined that only two synonymous single nucleotide polymorphisms across two genes (UL37/39) in the same isolate (from one host animal with a low disease severity score) were significantly associated (p ≤ 0.05) with assigned host respiratory and total disease severity score. No variants in any isolate were found to be significantly associated with assigned host ocular disease severity score. A concurrent analysis of missense mutations among the viral isolates identified three genes as being primarily involved in the observed genomic variation, but none were significantly associated with host disease severity scores. An ancestral state likelihood reconstruction was performed and determined that there was no evidence of a connection between host disease severity score and viral evolutionary state. We conclude from our results that the spectrum of host disease severity observed with FHV-1 is unlikely to be primarily related to viral genomic variations, and is instead due to host response and/or other factors.

In order to isolate buffaloes herpesvirus 1 (BuHV-1) from latently infected water buffalo (Bubalus bubalis), 16 buffalo heifers were selected from a herd. At first, animals were bled and their sera were tested by virus neutralization (VN) test, using bovine herpesvirus 1 (BoHV-1). According to the results of VN test and dexamethasone injection (0.1 mg/kg BW) for 5 consecutive days, the examined buffaloes were divided into 4 groups. Vaginal and nasal swabs were daily collected from all buffaloes from day 0 to 10 days later. Based on the cytopathic effects in cell culture, a herpesvirus was isolated only from nasal swabs of three seropositive buffaloes which they had received dexamethasone. The nasal swabs of these three buffaloes were also positive in PCR, using primers specific for ruminant herpesviruses gD gene. The identity of the isolated viruses was determined according to partial amino acid sequences of gD, deduced from the nucleotide sequences of the PCR products. On the basis of sequence alignment, phylogenetic analysis, and genetic distances, the three buffalo virus isolates were more closely related to BuHV-1 and BoHV-5 than to BoHV-1.

Caprine alphaherpesvirus 1 (CpHV-1) is a worldwide pathogen of goats and is closely related to Bovine alphaherpevirus 1 (BoHV-1). We herein studied the antigenic relationships of CpHV-1 with BoHV-1 and investigated the pathogenesis of CpHV-1 in kids and calves. Monoclonal antibody reactivity revealed that CpHV-1 and BoHV-1 share immunogenic epitopes in the major envelope glycoproteins gB, gC and gD. The antigenic relationship was further demonstrated by virus-neutralizing assays, in which CpHV-1 and BoHV-1 antisera presented varied degrees of cross-neutralization against the respective heterologous viruses. Although cross-neutralization was observed between both viruses and the heterologous antisera, BoHV-1 antisera neutralized CpHV-1 with higher efficiency than CpHV-1 antisera neutralized BoHV-1. Hence, the antigenic cross-reactivity between CpHV-1 and BoHV-1 should be considered upon serologic testing of goats and cattle in regions where the two viruses co-circulate. Intranasal (IN) inoculation of CpHV-1 (WI13-46 isolate) in seven seronegative kids resulted in efficient viral replication in the respiratory tract. Additionally, mild to moderate systemic and respiratory signs were observed, including apathy, hyperthermia, nasal discharge and respiratory distress. Dexamethasone administration to the inoculated kids between days 36 and 40 pi did not result in virus shedding in nasal secretions. However, latent infection had been established, as evidenced by the detection of CpHV-1 DNA in trigeminal ganglia and olfactory bulbs of kids euthanized at day 67 pi. Contrasting with the outcome of infection in kids, IN inoculation of CpHV-1 in calves did not result in productive infection as no virus replication or shedding were detected, and the animals did not develop clinical signs nor seroconverted. The animal experiments demonstrated that CpHV-1 was able to produce respiratory disease in kids, but did not replicate to detectable levels in calves., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Malignant catarrhal fever (MCF) can affect both domestic and wild artiodactyls. In a zoological setting, in which subclinical carriers and susceptible species are often housed in close proximity, the disease can prove fatal. This report describes a case of goat-associated MCF in a captive moose ( Alces alces). The diagnosis was confirmed by histopathology, which showed lymphocytic vasculitis in the brain and panuveitis, and by detection of caprine herpesvirus 2 DNA in tissues. Identical viral DNA sequences amplified from the clinically affected moose and from domestic, petting goats ( Capra aegagrus hircus) housed in the zoo suggest that the goats were the source for the virus transmutation. This is the first report, to our knowledge, of confirmed goat-associated MCF in any moose in North America and of the surveillance measures and procedures put in place to prevent additional spread of the disease.

A 2-y-old female Grant's zebra ( Equus quagga [ burchellii] boehmi) was presented with a clinical history of depression, anorexia, and weakness of 1-wk duration. Postmortem examination identified ulcers on the tongue and palate; a large abscess adjacent to the larynx; left lung consolidation; mild swelling, darkening, and congestion of the liver with accentuation of the lobular pattern; and edema and congestion of the distal small and large intestines. Histologic examination identified necrotizing bronchopneumonia, necrotizing hepatitis, nephritis, and enterocolitis. Eosinophilic intranuclear inclusions were detected in syncytial cells and degenerate bronchial epithelium in the lungs and in some hepatocytes associated with necrotic foci. Bacterial cultures of the lung, liver, and laryngeal abscess failed to detect any significant pathogen. Lung and liver tested positive for equine herpesvirus with neuropathogenic marker by real-time PCR. Subsequently, equine herpesvirus was isolated in tissue culture, and the entire viral DNA polymerase gene (ORF30) was sequenced. The zebra lung isolate had a very close nucleotide and amino acid sequence identity to equid alphaherpesvirus 9 (EHV-9; 99.6% and 99.8%, respectively) in contrast to the neuropathogenic T953 strain of EHV-1 (94.7% and 96.6%, respectively). Although zebras are considered the natural host for EHV-9, we document an unusual acute systemic, fatal EHV-9 infection in a 2-y-old Grant's zebra.

Signs of ocular infections like discharge and conjunctivitis occur commonly in cats in shelters and feline herpesvirus 1 (FHV-1), Chlamydia felis, Mycoplasma spp, and feline calicivirus (FCV) are thought to be the most common causes. While molecular assays are available to amplify nucleic acids of each of these agents as single tests or in panels, additional information is needed concerning whether the assay results can be used to predict response to treatment. The objectives of this study were to report results for conventional polymerase chain reaction (PCR) assays that amplify nucleic acids of FHV-1, Mycoplasma spp., C. felis, and FCV from cats with signs of acute ocular and upper respiratory infections in an animal shelter and to determine whether the results are associated with treatment responses to topical administration of cidofovir (anti-FHV-1) or oxytetracycline (anti-Mycoplasma spp. and C. felis). Conjunctival samples were collected from both eyes of 60 cats with ocular signs of disease. Total deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) were extracted from each sample and assayed for DNA of FHV-1, Mycoplasma spp., and C. felis and RNA of FCV by conventional PCR assays. Cats were randomized to be administered either oxytetracycline ointment or cidofovir drops in both eyes and a standardized ocular disease score system was used to determine a total ocular score for each cat prior to treatment on Day 0 and on Day 7. Nucleic acids of one or more agents were amplified from one or both eyes from 39 of 60 cats (65%). FHV-1 DNA (21 cats), Mycoplasma spp. DNA (25 cats) or FCV RNA (2 cats) were amplified most commonly. After treatment for 7 days, 32 of 60 cats (53.3%) were considered improved with 27 of 32 cats (84.4%) having ocular scores of 0 (21 cats) or 1 (6 cats). When the results of the FHV-1 PCR assay were compared to cidofovir treatment responses, the positive and negative predictive values of the assay were shown to be 29.4% and 60%, respectively. When the results of the Mycoplasma spp. PCR assay were compared to oxytetracycline treatment responses, the positive and negative predictive values of the assay were shown to be 40% and 38.5%, respectively. The predictive value of conventional PCR assay results for FHV-1 or Mycoplasma spp. DNA was low, suggesting that performing these tests to formulate a treatment protocol has minimal clinical utility in cats with suspected acute ocular infections., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Equid herpesvirus 8 (EHV-8), formerly known as asinine herpesvirus 3, is an alphaherpesvirus that is closely related to equid herpesviruses 1 and 9 (EHV-1 and EHV-9). The pathogenesis of EHV-8 is relatively little studied and to date has only been associated with respiratory disease in donkeys in Australia and horses in China. A single EHV-8 genome sequence has been generated for strain Wh in China, but is apparently incomplete and contains frameshifts in two genes. In this study, the complete genome sequences of four EHV-8 strains isolated in Ireland between 2003 and 2015 were determined by Illumina sequencing. Two of these strains were isolated from cases of abortion in horses, and were misdiagnosed initially as EHV-1, and two were isolated from donkeys, one with neurological disease. The four genome sequences are very similar to each other, exhibiting greater than 98.4% nucleotide identity, and their phylogenetic clustering together demonstrated that genomic diversity is not dependent on the host. Comparative genomic analysis revealed 24 of the 76 predicted protein sequences are completely conserved among the Irish EHV-8 strains. Evolutionary comparisons indicate that EHV-8 is phylogenetically closer to EHV-9 than it is to EHV-1. In summary, the first complete genome sequences of EHV-8 isolates from two host species over a twelve year period are reported. The current study suggests that EHV-8 can cause abortion in horses. The potential threat of EHV-8 to the horse industry and the possibility that donkeys may act as reservoirs of infection warrant further investigation.

We evaluated the Lyra Direct HSV 1+2/VZV multiplex real-time PCR assay for the detection and differentiation of herpes simplex virus 1 (HSV-1), HSV-2, and varicella-zoster virus (VZV) on 695 consecutive cutaneous and mucocutaneous lesion specimens. The intra-assay and interassay coefficient of variation values for the Lyra assay were 0.29 to 1.30% and 2.33 to 2.61%, respectively. The sensitivities, specificities, and positive and negative predictive values were 93.4 to 95.0%, 96.1 to 96.8%, 78.0 to 80.3%, and 99.0 to 99.1%, respectively, in comparison to those of viral culture. The values were further improved when a resolution analysis was performed with a laboratory-developed PCR assay., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)

Elephant endotheliotropic herpesviruses (EEHVs) can cause fatal hemorrhagic disease in juvenile Asian elephants (Elphas maximus); however, sporadic shedding of virus in trunk washes collected from healthy elephants also has been detected. Data regarding the relationship of viral loads in blood compared with trunk washes are lacking, and questions about whether elephants can undergo multiple infections with EEHVs have not been addressed previously. Real-time quantitative polymerase chain reaction was used to determine the kinetics of EEHV1 loads, and genotypic analysis was performed on EEHV1 DNA detected in various fluid samples obtained from five Asian elephants that survived detectable EEHV1 DNAemia on at least two separate occasions. In three elephants displaying clinical signs of illness, preclinical EEHV1 DNAemia was detectable, and peak whole-blood viral loads occurred 3-8 days after the onset of clinical signs. In two elephants with EEHV1 DNAemia that persisted for 7-21 days, no clinical signs of illness were observed. Detection of EEHV1 DNA in trunk washes peaked approximately 21 days after DNAemia, and viral genotypes detected during DNAemia matched those detected in subsequent trunk washes from the same elephant. In each of the five elephants, two distinct EEHV1 genotypes were identified in whole blood and trunk washes at different time points. In each case, these genotypes represented both an EEHV1A and an EEHV1B subtype. These data suggest that knowledge of viral loads could be useful for the management of elephants before or during clinical illness. Furthermore, sequential infection with both EEHV1 subtypes occurs in Asian elephants, suggesting that they do not elicit cross-protective sterilizing immunity. These data will be useful to individuals involved in the husbandry and clinical care of Asian elephants.

A 15-year-old Belgian gelding was referred for fever, depression, and respiratory distress. Lung biopsy revealed interstitial fibrosis consistent with chronic interstitial pneumonia. Equid herpesvirus 5 (EHV-5) DNA was detected by polymerase chain reaction (PCR) in bronchoalveolar lavage and biopsy specimens. A presumptive diagnosis of equine multinodular pulmonary fibrosis (EMPF) was made, and the horse was administered a systemic treatment with corticosteroids and antiviral drugs. Despite initial clinical improvement, 4 weeks later, the condition of the horse rapidly deteriorated, and the animal was euthanized. Postmortem examination confirmed the presumptive diagnosis of EMPF. The EHV-5 DNA load in different tissues was estimated using a quantitative real-time PCR. Lung had a remarkable viral load, higher than in other organs, especially within the pulmonary fibrotic nodules, and a linkage between high viral burden and the most severely affected tissues was observed. The results suggest that the quantitative real-time PCR is a useful tool to quantify the EHV-5 load in different organs and to understand the relationship between EHV-5 and EMPF. The bronchoalveolar lavage was determined to be a good clinical sample to estimate the EHV-5 load in lung.

The infectivity and pathology of equine herpesvirus 9 (EHV-9), a new neurotropic equine herpesvirus isolated from gazelles, was studied in hamsters experimentally infected via nasal, ocular, oral, intravenous (IV), or peritoneal routes. Clinically, all animals inoculated by the nasal route and ~25% inoculated by the oral and peritoneal routes showed neurological signs on days 3, 6, and 9 postinoculation (PI), respectively. Neurological signs were not observed in animals administered EHV-9 by the IV and ocular routes. With the exception of animals administered EHV-9 by the IV route, all infected animals had lymphocytic meningoencephalitis. Although there were a number of differences in the severity and distribution of the lesions depending on the route of inoculation, the basic features of lymphocytic meningoencephalitis caused by EHV-9 were common. Lesions consisted of neuronal necrosis, perivascular aggregates of lymphocytes, plasma cells, and neutrophils, gliosis, intranuclear inclusion bodies, and diffuse lymphocytic infiltrates in the meninges. Viral antigen was detected in degenerated neurons in infected animals inoculated by the nasal, ocular, oral, and peritoneal routes. The distribution of EHV-9 antigen was somewhat dependent on inoculation route. There were no microscopic abnormalities or viral antigen in animals treated by the IV route. This study provides new data about experimental EHV-9 infection in hamsters through routes other than the IV route. These results suggest that in the animals infected by the oral, ocular, and peritoneal routes, EHV-9 might travel to the brain through nerves, other than by the olfactory route, after initial propagation at the site of viral entry.

The lifelong infection by varicelloviruses is characterized by a fine balance between the host immune response and immune evasion strategies used by these viruses. Virus-derived peptides are presented to cytotoxic T lymphocytes by major histocompatibility complex (MHC) class I molecules. The transporter associated with antigen processing (TAP) transports the peptides from the cytosol into the endoplasmic reticulum, where the loading of MHC-I molecules occurs. The varicelloviruses bovine herpesvirus 1 (BoHV-1), pseudorabies virus, and equid herpesviruses 1 and 4 have been found to encode a UL49.5 protein that inhibits TAP-mediated peptide transport. To investigate to what extent UL49.5-mediated TAP inhibition is conserved within the family of Alphaherpesvirinae, the homologs of another five varicelloviruses, one mardivirus, and one iltovirus were studied. The UL49.5 proteins of BoHV-5, bubaline herpesvirus 1, cervid herpesvirus 1, and felid herpesvirus 1 were identified as potent TAP inhibitors. The varicella-zoster virus and simian varicellovirus UL49.5 proteins fail to block TAP; this is not due to the absence of viral cofactors that might assist in this process, since cells infected with these viruses did not show reduced TAP function either. The UL49.5 homologs of the mardivirus Marek's disease virus 1 and the iltovirus infectious laryngotracheitis virus did not block TAP, suggesting that the capacity to inhibit TAP via UL49.5 has been acquired by varicelloviruses only. A phylogenetic analysis of viruses that inhibit TAP through their UL49.5 proteins reveals an interesting hereditary pattern, pointing toward the presence of this capacity in defined clades within the genus Varicellovirus.

A 12-year-old female polar bear (Ursus maritimus) developed a sudden onset of muscle tremors, erratic circling, increased blinking, head shaking, and ptyalism, which progressed to partial and generalized seizures. Ancillary diagnostic tests were inconclusive, and the only significant laboratory finding was nonsuppurative pleocytosis of cerebrospinal fluid. Euthanasia was elected. Microscopic evaluation demonstrated multifocal, random nonsuppurative meningoencephalitis involving most prominently the rostral cerebral cortex, as well as the thalamus, midbrain, and rostral medulla. Lesions consisted of inflammation, neuronal necrosis, gliosis, and both neuronal and glial basophilic intranuclear inclusion bodies. Immunohistochemistry with a polyclonal antibody reactive to several equine herpesviruses was positive within affected areas of the brain, and polymerase chain reaction conclusively demonstrated the presence of only equine herpesvirus 9. The clinical and morphologic features of this case resemble other fatal herpesvirus encephalitides derived from interspecies transmission and underscore the need for extreme caution when managing wild or captive equids.

We describe an outbreak of infectious pustular vulvovaginitis caused by Caprine herpesvirus 1 (CpHV1) in a group of approximately 200, 8 month old virgin does that were imported to Victoria from New Zealand. CpHV1 was isolated in cell cultures from vaginal swabs from three of three affected does but not from two bucks that had been with the does. The identity of the virus as a herpesvirus was confirmed by negative stain electron microscopy. Restriction endonuclease DNA fingerprint analysis showed that the DNA fingerprints were similar, but not identical, to previously described CpHV1 isolates made in New Zealand, New South Wales, and in other parts of the world. Acute and convalescent phase sera from selected does supported the diagnosis of CpHV1 infection. It is most likely that the disease was initiated by reactivation of latent virus in at least one of four bucks that served the does, since each was positive for CpHV neutralising antibody when first tested. This is the first report of CpHV infectious pustular vulvovaginitis in goats in Victoria and to our knowledge appears to be one of the largest outbreaks recorded anywhere.

The major role of EHV-1 in equine abortion is widely reported in the literature but the contribution of EHV-2, EHV-3, EHV-4 or EHV-5 remains less well documented. The objective of this study is to evaluate the contribution of these five different EHVs to equine abortion in a variety of biological tissues using a consensus polymerase chain reaction (PCR). The test was validated for specificity and sensitivity in horses before screening specimens from 407 foetuses, stillbirths and premature foals collected over a 2.5-year interval. Positive results obtained with this assay were compared to other EHV type-specific PCR or by sequencing. EHV-1 was identified as the major cause of abortion in French mares (59/407 cases). However, there was evidence to suggest some variation in the potential of EHV-1 strains to induce abortion. Indeed, DNA samples from EHV-2 (in three cases) and EHV-5 (in one case) inferred a role of these viruses in abortion. The presence of viral DNA from EHV-3 or EHV-4 strains was not detected in the specimens studied. The data obtained suggest that the consensus herpesvirus PCR is an efficient screening tool. In association with a specific PCR, the test provides a rapid identification of the type of herpesvirus involved in abortion and is useful for routine diagnostic tests as it allows the identification of herpesviruses other than the EHV-1 strain.

The objectives of this study were to estimate the prevalence of equine herpesviruses (EHV) 1-5 in the nasal secretions (NS) of a cohort of 12 mares and their foals from birth to 6 months of age, estimate the prevalence of EHV-1-5 infection of peripheral blood mononuclear cells (PBMC) of selected foals, and investigate phylogenetic relationships amongst the various strains of EHV-2 and 5. Virus-specific PCR assays were used to detect EHV-1-5 in NS and PBMC. A homologous portion of the glycoprotein B (gB) gene of the various strains of EHV-2 and 5 was sequenced and compared. EHV-2, 4, and 5 were all detected in NS from the horses, but only EHV-4 was associated with respiratory disease (P=0.005). EHV-2 and 5 infections were both common, but foals shed EHV-2 in their NS earlier in life than EHV-5 (P=0.01). Latent EHV-2 and 5 infections were detected in the PBMC of 75 and 88%, respectively, of the foals at approximately 6 months of age. The strains of EHV-2 shed in the NS of individual horses were more genetically heterogeneous than the strains of EHV-5 (95.5-99.3% versus 98.8-99.3% nucleotide identity, respectively). One-month-old foals typically shed strains of EHV-2 that were identical to those infecting their dams whereas older foals often shed virus strains that were different from those of their dams. Although herpesvirus infections were ubiquitous in this cohort of horses, there were distinct clinical consequences and clear epidemiological differences between infections with the different viruses.

Elk herpesvirus (ElkHV) from North American elk (wapiti, Cervus elaphus nelsoni) is a recently identified alphaherpesvirus related to bovine herpesvirus-1 (BHV-1). In this study, we determined its relationship with European cervid herpesviruses: cervid herpesvirus-1 (CerHV-1) from red deer and rangiferine herpesvirus (RanHV) from reindeer. For phylogenetic analysis, genes for the gC and gD proteins of these viruses were sequenced. These genes demonstrated an extremely high GC content (76-79%). Genetically, ElkHV was found to be closely related to CerHV-1 and both viruses are more closely related to BHV-1 than to RanHV. Antigenically, the same relationships were found. ElkHV shares common neutralizing epitopes with both CerHV-1 and RanHV. A total of 10 epitopes were defined on the gB, gC and gD proteins of these viruses, including a shared neutralizing epitope on gD. The results indicate that ElkHV and CerHV-1 have diverged from a common ancestor virus. Cervid herpesviruses may be useful in determination of evolutionary rates of change for alphaherpesvirus genes.

Fifty-four ocular and forty-six pharyngeal swabs, collected from 54 cats with respiratory syndrome, were analyzed by duplex-PCR to evaluate the presence of Feline Herpesvirus type 1 and Chlamydophila spp. Both pathogens are in the population of cats and as four cats were positive only in ocular swabs and three only in pharyngeal ones, it is deduced that a correct diagnostic approach has to foresee the dispatch to the laboratory of both swabs. Furthermore, all chlamydophila strains analysed by endonuclease restriction were classified as Chlamydophila felis.

Cattle are the natural host of herpesviruses. Since now four different bovine viruses have been described as members of the family Herpesviridae. The prototype of the bovine herpesviruses, Bovine Herpesvirus type 1 (BHV-1), is the causative agent of infectious bovine rhinotracheitis (IBR), infectious pustular vulvovaginitis (IPV) and infectious balanoposthitis (IBP). The related BHV-5 is an exotic neurovirulent agent and like BHV-1 a member of the genus Varicellovirus, within the subfamily Alphaherpesvirinae. BHV-2, also an alphaherpesvirus but grouped into the genus Simplexvirus is the causative agent of bovine herpes mammilitis and pseudolumpy skin disease. In contrast, BHV-4, a member of the subfamily Gammaherpesvirinae, is not known to cause any disease. Beside bovine herpesviruses there are few other herpesviruses which can infect cattle. Infections of cattle with these herpesviruses have either clinical or diagnostic importance, based on a close antigenic relationship to BHV-1 of some ruminant herpesviruses. This article deals with the molecular virology of bovine herpesviruses and the pathogenesis of bovine herpesvirus infections and provides an overview over herpesviruses that can infect cattle.

In this study, a multiplex polymerase chain reaction (PCR) procedure was developed for differentiation of strains and field isolates of equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4). Specific oli-gonucleotide primers were combined to amplify the thymidine kinase (TK) gene region of EHV-1 and EHV-4, which would yield fragments of different lengths for each virus in the same amplification reaction. The specificity of the largest PCR amplicon for EHV-4 was confirmed by restriction digestion with HindIII. The multiplex PCR proved to be a fast and sensitive method for typing EHV-1 and EHV-4 isolates and for detection and differentiation of both viruses in field samples in which infectious virus is no longer available. The sensitivity was improved by combining cycling optimization and visualization of PCR products in ethidium bromide and silver-stained acrylamide gels.