RESUMO
The antigenic properties of H3N8 equine influenza virus from the Swedish epizootic of 1991 differ from those of A/eq 2/Fontainebleau/79 (representative of the Swedish vaccine strain) in hemagglutination inhibition tests. The amino acid sequence of the hemagglutinin (HA) of an isolate from the 1991 outbreak was deduced from the nucleotide sequence and comparison was made to the A/eq 2/Fontainebleau/79 strain. Twenty-three amino acid substitutions were found, 10 mapping onto areas of the HA known to bind antibodies in human H3 influenza viruses. The amino acid changes together with the serological data suggest that a major antigenic drift has taken place in equine H3N8 viruses in Sweden and we conclude that recent strains of the virus must be incorporated into vaccines on a regular basis if epizootics of equine influenza are to be controlled in the future.
Assuntos
Antígenos Virais/genética , Variação Genética , Vírus da Influenza A/genética , Sequência de Aminoácidos , Animais , Antígenos Virais/imunologia , Sequência de Bases , Embrião de Galinha , DNA Viral , Surtos de Doenças , Epitopos , Genes Virais , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Hemaglutininas Virais/genética , Hemaglutininas Virais/imunologia , Doenças dos Cavalos/epidemiologia , Cavalos , Vírus da Influenza A/imunologia , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/veterinária , Homologia de Sequência de Aminoácidos , Suécia/epidemiologiaRESUMO
The antigenic properties of H3N8 influenza viruses isolated from outbreaks of equine influenza in Sweden between 1979 and 1991 have been studied in hemagglutination inhibition tests with polyclonal and monoclonal antisera, and antigenic drift of the virus has been demonstrated. To clarify the basis of the antigenic drift, amino acid sequences of the globular head regions (HA1) of the hemagglutinin membrane glycoproteins of virus strains from 1979, 1984, 1988 and 1990 have been deduced from the nucleotide sequences of the hemagglutinin genes, and the sequence information has been used to construct a phylogenetic tree of H3N8 equine influenza strains. Several strains from previous studies have been included to give a clearer picture of viral evolution in an international context.
Assuntos
Evolução Biológica , Hemaglutininas Virais/genética , Doenças dos Cavalos/virologia , Vírus da Influenza A Subtipo H3N8 , Vírus da Influenza A/genética , Infecções por Orthomyxoviridae/veterinária , Sequência de Aminoácidos , Animais , Anticorpos , Anticorpos Monoclonais , Sequência de Bases , Frequência do Gene , Testes de Inibição da Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Cavalos , Vírus da Influenza A/isolamento & purificação , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/virologia , RNA Viral/isolamento & purificação , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Suécia , Fatores de Tempo , Proteínas do Envelope Viral/genéticaRESUMO
An indirect enzyme-linked immunosorbent assay (ELISA) was developed to detect antibodies to BLV in milk and serum (Juntti et al., 1989). The conjugate consists of a monoclonal anti-bovine IgG1 and IgG2 labelled with horseradish peroxidase (HRP). The indirect ELISA was calibrated with EEC reference serum E 4. Standard serum E 4 was scored positive when diluted 8192 times in negative milk and between 12,800 and 25,600 times in negative serum. The sensitivity and specificity of the indirect ELISA relative to the agar gel immunodiffusion test (AGID) were 100% and 99.8%, respectively. ELISA results for milk and sera from 614 dairy cows agreed to 100%. The absorbance value in bulk milk could be used to roughly predict the rate of BLV infection among lactating cows in a herd. An infection rate of 4 to 5% in a herd could be detected in the ELISA. Results were applied in a nation-wide screening of more than 24,000 bulk-milk samples, and the subsequent introduction of an eradication programme for BLV. The aim is to eliminate the infection from Swedish herds in 5 to 10 years.
Assuntos
Anticorpos Antivirais/análise , Ensaio de Imunoadsorção Enzimática/métodos , Vírus da Leucemia Bovina/imunologia , Leite/microbiologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/sangue , Calibragem , Bovinos , Células Cultivadas , Estudos de Avaliação como Assunto , Imunoglobulina G/imunologia , Mastite/patologia , Propilenoglicóis , Sensibilidade e EspecificidadeRESUMO
Primers and probes were selected from the gene encoding glycoprotein 13 (gp 13) of equine herpesvirus 1 (EHV-1). The polymerase chain reaction (PCR) was run on infected and noninfected cultured cells and on 63 specimens from 29 aborted equine fetuses. The results were evaluated by electrophoresis and dot-blot hybridization using an oligonucleotide probe labeled with biotin. In the infected samples electrophoresis showed a PCR product of about 280 base pairs. The dot-blot hybridization confirmed that this product contained EHV-1 DNA sequences. PCR took 4 h and hybridization another 14 h; the results were thus achieved within 24 h and were highly specific for EHV-1. Close concordance was found between the results of PCR and virus isolation.
Assuntos
Aborto Animal/diagnóstico , DNA Viral/análise , Infecções por Herpesviridae/veterinária , Herpesviridae/genética , Herpesvirus Equídeo 1/genética , Doenças dos Cavalos/diagnóstico , Animais , Eletroforese em Gel de Ágar , Feminino , Feto/microbiologia , Infecções por Herpesviridae/diagnóstico , Herpesvirus Equídeo 1/isolamento & purificação , Cavalos , Hibridização de Ácido Nucleico , Sondas de Oligonucleotídeos , Placenta/microbiologia , Reação em Cadeia da Polimerase , GravidezRESUMO
Comparative analysis by RNA oligonucleotide fingerprints of total genomic RNA as well as the individual RNA segments of equine 2 influenza A virus strains from 1963, 1968, 1979, 1984, 1987 and 1988 revealed genetic diversity. Strains from the epizootic outbreak during 1978-1979 showed minor differences among their genomes. The Swedish isolates from 1979 up to 1988 showed increasing genomic heterogeneity indicating genetic drift.
Assuntos
Frequência do Gene , Vírus da Influenza A Subtipo H3N8 , Vírus da Influenza A/genética , Oligonucleotídeos/análise , RNA Viral/análise , Animais , Anticorpos Antivirais/análise , Reações Cruzadas , Testes de Inibição da Hemaglutinação , Vírus da Influenza A/imunologia , Mapeamento de Nucleotídeos , Homologia de Sequência do Ácido NucleicoRESUMO
Equine arteritis virus (EAV), a non-arthropod borne togavirus, has been shown to have a global distribution. To date, no major antigenic variation has been demonstrated between EAV isolates from different geographic origins. In this study, the genomic RNA of EAV isolates obtained from horses of different breeds in various countries around the world was oligonucleotide fingerprinted. Comparisons of these fingerprints were used to determine the extent of genomic variation among such isolates. Comparisons among isolates from North American horses revealed, for the most part, oligonucleotide homologies of less than 60%. Only 29 of the 98 comparisons revealed greater than 60% oligonucleotide homology. Nonetheless, several comparisons indicated a close epidemiologic relationship between isolates from horses of different breeds located in different states. Though all European isolates were of Standardbred origin and were from horses located in northern European countries, the majority had oligonucleotide homologies of less than 60%. Where oligonucleotide homology was apparent, it was, with one exception, greater than 70%. The two isolates from New Zealand had 93.2% oligonucleotide homology. This is indicative of an extremely close epidemiologic relationship. Comparisons between EAV isolates from around the world revealed oligonucleotide homologies between viruses from North America, Europe and New Zealand. In several instances, this homology was greater than 70% and in one case greater than 80%. No oligonucleotide homology was evident in comparisons involving the virus from South Africa. The high level of genomic conservation between certain EAV isolates of disparate geographic origins may reflect dissemination of the virus associated with the international movement of horses. The extent of genomic variation demonstrated between most of the EAV isolates used in this study confirms the need for further investigation of genomic heterogeneity among strains of this virus before techniques that rely upon nucleic acid hybridization can be effectively applied as diagnostic procedures.
Assuntos
Arterite/veterinária , Equartevirus/genética , Variação Genética , Doenças dos Cavalos/microbiologia , Infecções por Togaviridae/veterinária , Animais , Arterite/epidemiologia , Arterite/microbiologia , Autorradiografia , Cruzamento , Eletroforese em Gel Bidimensional , Europa (Continente)/epidemiologia , Doenças dos Cavalos/epidemiologia , Cavalos , Nova Zelândia/epidemiologia , América do Norte/epidemiologia , Oligonucleotídeos/análise , RNA Viral/análise , Homologia de Sequência do Ácido Nucleico , África do Sul/epidemiologia , Infecções por Togaviridae/epidemiologia , Infecções por Togaviridae/microbiologiaRESUMO
A blocking enzyme-linked immunosorbent assay (ELISA) was developed to detect antibodies to equine herpesvirus 2 in serum samples of horses. By measuring the binding to a single epitope, this blocking ELISA gives a good picture of the antibody status in the animal. The test is based on a monoclonal antibody with neutralizing activity and had a sensitivity of 94% and a specificity of 100%. Antibodies due to newly acquired infection in foals were successfully detected with this blocking ELISA.
Assuntos
Anticorpos Antivirais/análise , Ensaio de Imunoadsorção Enzimática/veterinária , Infecções por Herpesviridae/veterinária , Rhadinovirus/imunologia , Infecções Tumorais por Vírus/veterinária , Animais , Anticorpos Monoclonais , Técnicas de Cultura de Células , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/imunologia , Cavalos , Masculino , Coelhos , Sensibilidade e Especificidade , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/imunologiaRESUMO
Six hundred and fifteen serum samples obtained from cows in five districts of Apure State, Venezuela, were tested by ELISA for antibodies to bovine virus diarrhoea virus (BVDV). The same samples were also ELISA-tested for antibodies to bovine herpesvirus type 1 (BHV-1) and bovine respiratory syncytial virus (BRSV). Additionally, the haemagglutination-inhibition (HI) test was used for detecting antibodies to parainfluenza virus type 3 (PIV-3). Overall, seroprevalence to BVDV was 36+/-7% (SE); seroprevalence varied by district (19-42%). BHV-1 seroprevalence was 67+/-4%; variation by district was similar to that of BVDV. However, the first 80 serum samples tested by BHV-1 ELISA all had a strong background reaction with the control antigen. Therefore, these sera were adsorbed to a homogenate of non-infected bovine kidney cell line (MDBK) and retested by ELISA. The non-specific reactivity was significantly reduced (p<0.001 by Wilcoxon's signed-rank test). Compared to the virus-neutralisation (VN) test, the adsorbed BHV-1 ELISA showed 94% agreement and gave a kappa value of 0.84, indicating that the adsorption did not interfere with test accuracy. Seroprevalence against BRSV was 85+/-3%, and showed differences across districts. Most of the cows (94+/-2%) were seropositive to PIV-3, and there were no significant differences among districts.
Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/epidemiologia , Vírus da Diarreia Viral Bovina/imunologia , Infecções por Herpesviridae/epidemiologia , Herpesvirus Bovino 1/imunologia , Infecções por Vírus Respiratório Sincicial/veterinária , Vírus Sincicial Respiratório Bovino/imunologia , Infecções por Respirovirus/veterinária , Respirovirus/imunologia , Animais , Anticorpos Antivirais/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/prevenção & controle , Bovinos , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Testes de Inibição da Hemaglutinação/veterinária , Infecções por Herpesviridae/prevenção & controle , Testes de Neutralização/veterinária , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Infecções por Respirovirus/epidemiologia , Infecções por Respirovirus/prevenção & controle , Estudos Soroepidemiológicos , Venezuela/epidemiologiaRESUMO
The shedding, tissue distribution and quasispecies composition of feline coronaviruses were studied in naturally and experimentally infected cats. The infection remained subclinical, but the majority of the animals shed the virus via faeces throughout the experiment. Sequences corresponding to the viral nucleocapsid region were amplified by reverse-transcription polymerase chain reaction from the cortex, dura mater, pancreas, lungs, third eyelid, and the heart muscle in four cases. Interestingly, the ORF7b viral region - a supposed virulence factor - was detected in fewer organs, raising the possibility that this region can be affected by deletions during virus replication in vivo. It is demonstrated that the composition of the viral quasispecies differs between organs, and that genomic regions with different functions undergo distinct processes of selection, which should be considered during the evolution of feline coronaviruses.
Assuntos
Doenças do Gato/virologia , Infecções por Coronavirus/veterinária , Animais , Gatos , Coronavirus/genética , Coronavirus/isolamento & purificação , Feminino , Masculino , Polimorfismo Conformacional de Fita Simples , Distribuição Aleatória , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Carga Viral/veterináriaRESUMO
The prevalence and phylogeny of feline coronaviruses were studied in urban cat populations by sampling of 113 clinically healthy cats. Rectal swab samples were subjected to a nested reverse-transcription polymerase chain reaction, specific for the conservative nucleocapsid region of the virus genome. More than 30% of the sampled animals proved positive for the presence of feline coronaviruses. The nucleotide sequences of amplified 440 bp products were determined, aligned and the phylogenetic analysis revealed noticeable genetic clusters among the prevalent feline coronaviruses in the surveyed geographic area. These findings will hopefully contribute to the elucidation of the epidemiology of feline infectious peritonitis.
Assuntos
Gatos/virologia , Coronavirus/genética , Coronavirus/isolamento & purificação , Animais , DNA Complementar/química , Filogenia , Reação em Cadeia da Polimerase , Reto/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , População UrbanaRESUMO
Serum antibody titers to canine parvovirus (CPV), canine adenovirus-1 (CAV-1), and canine distemper virus (CDV) were measured in dogs with known immunization status. The dogs represented 3 groups: nonvaccinated dogs less than 12 months old; vaccinated dogs less than 12 months old; and adult dogs greater than 12 months old. For practical reasons, the population from which the specimens were obtained could be considered as free from natural infection with CAV-1 and CDV. In nonvaccinated dogs less than 12 months old, antibodies against all 3 viruses were measured at the time the dogs were given their first vaccination. Altogether, 50.7% of the dogs had titer greater than or equal to 1:10 to CPV, and 26.1 and 46.2% had titer greater than or equal to 1:8 to CAV-1 and CDV, respectively. The concentration of maternal antibody seemed to be of major importance for failure of immunization with use of inactivated CPV vaccine, but not with CAV-1 and CDV vaccination. In dogs less than 12 months old and vaccinated against CPV infection with inactivated virus, only 11.5% had titer greater than or equal to 1:80. In dogs vaccinated against infectious canine hepatitis and canine distemper, 63.2 and 78.3%, respectively, had titer greater than or equal to 1:16. In adult dogs greater than 2 months old and vaccinated against CPV infection, less than 50% had titer greater than or equal to 1:80, regardless of time after vaccination. There was no significant difference in titer between vaccinated and nonvaccinated dogs.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Adenoviridae/imunologia , Anticorpos Antivirais/análise , Vírus da Cinomose Canina/imunologia , Cães/imunologia , Parvoviridae/imunologia , Vacinação/veterinária , Animais , Feminino , Masculino , SuéciaRESUMO
Immunogenic potency of a killed feline panleukopenia virus vaccine against canine parvoviral enteritis in dogs was examined. The vaccine elicited hemagglutination-inhibition antibodies to canine parvovirus (CPV) in all of the 72 dogs which were vaccinated. The vaccine was protective in dogs against both experimentally induced and naturally occurring CPV-induced disease. By statistical analysis, 4 weeks was found to be the optimal spacing between 2 vaccinal doses resulting in hemagglutination-inhibition antibody titers up to 1:5,120. Adverse reactions to the vaccine were not observed. Atypical lymphocytes were found consistently in the CPV-infected control dogs.
Assuntos
Doenças do Cão/prevenção & controle , Enterite/veterinária , Vírus da Panleucopenia Felina/imunologia , Parvoviridae/imunologia , Vacinas Virais/imunologia , Viroses/veterinária , Animais , Anticorpos Antivirais/análise , Doenças do Cão/imunologia , Cães , Enterite/imunologia , Enterite/prevenção & controle , Feminino , Testes de Inibição da Hemaglutinação/veterinária , Testes de Hemaglutinação/veterinária , Masculino , Vacinação/veterinária , Viroses/imunologia , Viroses/prevenção & controleRESUMO
An enzyme-linked immunosorbent assay (ELISA) system was developed for the detection of canine parvovirus (CPV) or CPV antigen in dog faeces and two other ELISA systems were developed for the detection of CPV-specific antibodies in dog sera. The ELISA's were based on the use of CPV-specific mouse monoclonal antibodies, which recognise different epitopes of the haemagglutinin of CPV and which also neutralise the virus. A double antibody sandwich (DAS) ELISA for the detection of CPV in dog faeces was compared with the haemagglutination (HA) test. The DAS-ELISA proved to be more specific, sensitive and easier to perform than the HA assay. An indirect ELISA and a competitive ELISA for the detection of CPV-specific antibodies in dog sera were compared with the haemagglutination inhibition (HI) test. Both ELISA systems proved to be specific and easy-to-use methods for the detection of CPV-specific antibodies. The indirect ELISA, specially, proved to be more sensitive than the HI test. The higher sensitivity and specificity of the ELISA's as compared to HA and HI tests, and their ease of use, make them suitable for routine use in the serology and diagnosis of CPV infections.
Assuntos
Anticorpos Antivirais/análise , Antígenos Virais/análise , Doenças do Cão/diagnóstico , Infecções por Parvoviridae/veterinária , Parvoviridae/imunologia , Animais , Anticorpos Monoclonais , Linhagem Celular , Cães , Ensaio de Imunoadsorção Enzimática , Fezes/microbiologia , Testes de Inibição da Hemaglutinação , Testes de Hemaglutinação , Infecções por Parvoviridae/diagnóstico , Organismos Livres de Patógenos EspecíficosRESUMO
Six cases of paresis occurred in a Swedish stud with 48 mares and a stallion. Complement-fixation tests revealed a recent infection with EHV-1 in most horses of the stud. Serumneutralisation tests showed rapid antibody-titre increases during the course of the disease. This type of antibody response was interpreted as induced by reinfection or, possibly, recurrent infection. Two diseased mares were sacrificed. No virus could be isolated from their central nervous system (CNS), liver or spleen, but there is a presumptive evidence for the presence of an antigen specific to EHV-1 in the CNS and liver. Neutralising antibodies to EHV-1 were demonstrated in the liver and kidneys following elution by acidification of the tissues. No such antibodies could be demonstrated in the brain and spinal cord. A possible reason for this failure is discussed.
Assuntos
Infecções por Herpesviridae/veterinária , Herpesviridae/imunologia , Herpesvirus Equídeo 1/imunologia , Doenças dos Cavalos/imunologia , Paraplegia/veterinária , Animais , Sistema Nervoso Central/imunologia , Testes de Fixação de Complemento , Surtos de Doenças/veterinária , Feminino , Infecções por Herpesviridae/imunologia , Cavalos , Rim/imunologia , Fígado/imunologia , Masculino , Paraplegia/imunologia , Baço/imunologiaRESUMO
The prevalence of antibodies against Bordetella bronchiseptica and canine parainfluenza-2 virus (CPiV-2) was investigated in a population of 302 pet dogs in Sweden. Sera were analysed for B bronchiseptica-specific immunoglobulin G by means of an ELISA, and for CPiV-2 specific neutralising antibody by means of a haemagglutination inhibition test. B bronchiseptica had a seroprevalence of 22 per cent and CPiV-2 had a seroprevalence of 28 per cent. The two pathogens did not appear to circulate together. The crowding of dogs together was significantly associated with the seroprevalence of CPiV-2, but not with the seroprevalence of B bronchiseptica. The dogs' ages, gender or their Fédération Cynologique Internationale breed group affiliation was not correlated with the seroprevalence of either pathogen.
Assuntos
Infecções por Bordetella/veterinária , Bordetella bronchiseptica/imunologia , Doenças do Cão/imunologia , Infecções por Paramyxoviridae/veterinária , Animais , Infecções por Bordetella/epidemiologia , Infecções por Bordetella/imunologia , Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Cães , Feminino , Masculino , Infecções por Paramyxoviridae/epidemiologia , Infecções por Paramyxoviridae/imunologia , Prevalência , Estudos Soroepidemiológicos , Suécia/epidemiologiaRESUMO
The inclination of dog owners to vaccinate was investigated by sending a questionnaire to randomly selected Swedish dog-owning households. According to the owners (n = 538), 86.7% of the dogs had been vaccinated against CPV and 95.8% had been vaccinated against CD/ICH. The inclination to vaccinate mixed breeds was significantly lower than the inclination to vaccinate pure-bred dogs. In a second study titres of CPV, CD and CAV-1 virus antibodies were measured in 176 randomly selected dogs with known vaccination histories. CPV antibody titres > or = 1:80 were detected in 70.9% of the CPV vaccinated dogs. There was a significant difference in the fraction of dogs with CPV titre > or = 1:80 between the group last vaccinated with live attenuated vaccine and the group last vaccinated with inactivated vaccine. Titres of CD and CAV-1 virus antibodies > or = 1:16 were found in 86.1% and 91.6% of the vaccinated dogs respectively. The fraction of dogs with CAV-1 antibody titres > or = 1:16 was significantly greater in the group that received inactivated CAV-1 vaccine than in the group vaccinated with attenuated live CAV-2 vaccine. Approximately 50% of the dogs were booster vaccinated against all 3 diseases at one year of age.
Assuntos
Cinomose/prevenção & controle , Doenças do Cão/prevenção & controle , Hepatite Infecciosa Canina/prevenção & controle , Infecções por Parvoviridae/prevenção & controle , Infecções por Parvoviridae/veterinária , Vacinação/veterinária , Animais , Formação de Anticorpos , Cinomose/imunologia , Doenças do Cão/imunologia , Cães , Feminino , Hepatite Infecciosa Canina/imunologia , Masculino , Infecções por Parvoviridae/imunologia , Inquéritos e Questionários , SuéciaRESUMO
The acute phase protein serum amyloid A (SAA) has proven potentially useful as an inflammatory marker in the horse, but the knowledge of SAA responses in viral diseases is limited. The aim of this study was to evaluate SAA as a marker for acute equine influenza A2 (H3N8) virus infection. This is a highly contagious, serious condition that inflicts suffering on affected horses and predisposes them to secondary bacterial infections and impaired performance. Seventy horses, suffering from equine influenza, as verified by clinical signs and seroconversion, were sampled in the acute (the first 48 h) and convalescent (days 11-22) stages of the disease, and SAA concentrations were determined. Clinical signs and rectal temperature were recorded. Secondary infections, that could have influenced SAA concentrations, were clinically suspected in 4 horses. SAA concentrations were higher in the acute stage than in the convalescent stage, and there was a statistically positive relationship between acute stage SAA concentrations and clinical signs and between acute stage SAA concentrations and maximal rectal temperature. Horses sampled early in the acute stage had lower SAA concentrations than those sampled later, indicating increasing concentrations during the first 48 h. There was a statistically positive relationship between convalescent SAA concentrations and degree of clinical signs during the disease process. The results of this investigation indicate that equine SAA responds to equine influenza infection by increasing in concentration during the first 48 h of clinical signs and returning to baseline within 11-22 days in uncomplicated cases.
Assuntos
Proteínas de Fase Aguda/imunologia , Doenças dos Cavalos/imunologia , Vírus da Influenza A/imunologia , Infecções por Orthomyxoviridae/veterinária , Proteína Amiloide A Sérica/imunologia , Proteínas de Fase Aguda/biossíntese , Fatores Etários , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/sangue , Biomarcadores/sangue , Temperatura Corporal , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Testes de Inibição da Hemaglutinação/veterinária , Doenças dos Cavalos/virologia , Cavalos , Técnicas Imunoenzimáticas/veterinária , Modelos Lineares , Masculino , Mucosa Nasal/virologia , Infecções por Orthomyxoviridae/sangue , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Distribuição Aleatória , Valores de Referência , Proteína Amiloide A Sérica/biossíntese , Fatores SexuaisRESUMO
Canine herpes virus-1 (CHV1) causes a fatal hemorrhagic disease in neonatal puppies and is associated with reproductive problems in female dogs. This serologic study was conducted to assess the seroprevalence of CHV1 infection in Norway. Blood samples were collected from clinically healthy dogs (n = 436) one yr of age and older of both genders, supplied by four small animal clinics (A, B, C and D) in different parts of the country. The immunoperoxidase monolayer assay was used for testing of CHV1 antibodies. Serum titers were recorded as the reciprocal value of the highest dilution producing specific cell staining. Titers equal to or above 80 were considered positive for exposure to CHV1. In total, 80.0% of the dogs had titers ≥80 and were classified as positive. Mean age for seronegative dogs was 4.7 yrs (95% CI 4.1-5.4) and for seropositive dogs 5.0 yrs (95% CI 4.7-5.4). Of the dogs, 32.8% displayed a weakly positive titer of 80, whereas 41.5 and 5.7% fell into the moderately (titer 160 and 320) and strongly (titer ≥640) positive categories, respectively. No association was demonstrated when comparing CHV1 antibody titers to gender or reproductive parameters like previous matings, pregnancies, births or number of puppies born. Age, visit in foreign countries and clinic explained together 78% of the variation in antibody titer categories. The percentage of positive samples differed significantly between the four clinics (A 98%, B 58.5%, C 74.6%, D 89.5%). A reasonable explanation for this finding has not been established. No information about an ongoing outbreak of CHV1 infection was available. In conclusion, this study strongly indicates that CHV1 infection is endemic in the dog population of Norway. There are significant differences in seroprevalence between geographic regions in the country.