RESUMO
(1) Background: Antibody testing is commonly used to assess a dog's immune status. For detection of antibodies against canine adenoviruses (CAVs), one point-of-care (POC) test is available. This study assessed the POC test´s performance. (2) Methods: Sera of 198 privately owned dogs and 40 specific pathogen-free (SPF) dogs were included. The reference standard for detection of anti-CAV antibodies was virus neutralization (VN) using CAV-1 and CAV-2 antigens. Specificity, sensitivity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy (OA) of the POC test were assessed. Specificity was considered most important. (3) Results: Prevalence of CAV-1 neutralizing antibodies (≥10) was 76% (182/238) in all dogs, 92% (182/198) in the subgroup of privately owned dogs, and 0% (0/40) in SPF dogs. Prevalence of CAV-2 neutralizing antibodies (≥10) was 76% (181/238) in all dogs, 91% (181/198) in privately owned dogs, and 0% (0/40) in SPF dogs. Specificity for detection of CAV-1 antibodies was lower (overall dogs, 88%; privately owned dogs, 56%; SPF dogs, 100%) compared with specificity for detection of CAV-2 antibodies (overall dogs, 90%; privately owned dogs, 65%; SPF dogs, 100%). (4) Conclusions: Since false positive results will lead to potentially unprotected dogs not being vaccinated, specificity should be improved to reliably detect anti-CAV antibodies that prevent infectious canine hepatitis in dogs.
Assuntos
Infecções por Adenoviridae/veterinária , Adenovirus Caninos/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Doenças do Cão/imunologia , Testes Imediatos , Infecções por Adenoviridae/imunologia , Vacinas contra Adenovirus , Animais , Cães , Ensaio de Imunoadsorção Enzimática , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Masculino , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Vacinação/veterináriaRESUMO
BACKGROUND: Re-vaccination against canine adenovirus (CAV) is performed in ≤3-year-intervals but their necessity is unknown. The study determined anti-CAV antibodies within 28 days of re-vaccination and factors associated with the absence of antibodies and vaccination response. METHODS: Ninety-seven healthy adult dogs (last vaccination ≥12 months) were re-vaccinated with a modified live CAV-2 vaccine. Anti-CAV antibodies were measured before vaccination (day 0), and after re-vaccination (day 7, 28) by virus neutralization. A ≥4-fold titer increase was defined as vaccination response. Fisher's exact test and multivariate regression analysis were performed to determine factors associated with the absence of antibodies and vaccination response. RESULTS: Totally, 87% of dogs (90/97; 95% CI: 85.61-96.70) had anti-CAV antibodies (≥10) before re-vaccination. Vaccination response was observed in 6% of dogs (6/97; 95% CI: 2.60-13.11). Time since last vaccination (>3-5 years, OR = 9.375, p = 0.020; >5 years, OR= 25.000, p = 0.006) was associated with a lack of antibodies. Dogs from urban areas were more likely to respond to vaccination (p = 0.037). CONCLUSION: Many dogs had anti-CAV pre-vaccination antibodies, even those with an incomplete vaccination series. Most dogs did not respond to re-vaccination. Based on this study, dogs should be re-vaccinated every 3 years or antibodies should be determined.
Assuntos
Adenovirus Caninos/imunologia , Anticorpos Antivirais/sangue , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Cães , Feminino , Imunização Secundária , Masculino , Vacinas Virais/efeitos adversosRESUMO
BACKGROUND: Viral diseases are a major cause of morbidity and mortality in puppies. There is a belief among veterinary practitioners and even educational institutions that the vaccines made in Brazil against canine distemper virus (CDV), canine parvovirus (CPV) and canine adenovirus (CAV) are ineffective or only partially effective. OBJECTIVES: This study aimed at comparing the immunity of two multivalent vaccines in adult dogs in the city of Uberlândia, Minas Gerais state, Brazil. METHODS: The study was carried out at the Animal Protection Association and a total of 60 adult mongrel dogs were selected and divided into two groups. Group A was immunized with two doses of Elevencell® vaccine and Group B received two doses of imported vaccine from the United States; each group was made up of 14 females and 14 males. RESULTS: In group A, the Elevencell vaccine generated a protective antibody titre against CDV in 26 out of 28 subjects (92.85%), CPV in 24 out of 28 subjects (85.71%) and CAV in 26 out of 28 subjects (92.85%). In group B, the imported US vaccine generated a protective antibody titre against CDV in 22 out of 28 subjects (78.57), CPV in 21 out of 28 subjects (75%) and CAV in 25 out of 28 subjects (89.28%). There was no statistical difference between titres generated between vaccine types for any of the three diseases tested. CONCLUSION: Elevencell vaccine titres were not inferior to the imported US vaccine in conferring protective titres against CDV, CPV and CAH, which confirms the efficacy of this product.
Assuntos
Adenovirus Caninos/imunologia , Vírus da Cinomose Canina/imunologia , Cinomose/prevenção & controle , Hepatite Infecciosa Canina/prevenção & controle , Infecções por Parvoviridae/prevenção & controle , Parvovirus Canino/imunologia , Vacinação/veterinária , Vacinas Virais/administração & dosagem , Vacinas contra Adenovirus/administração & dosagem , Animais , Brasil , Cães , Método Duplo-Cego , Feminino , Masculino , Vacinas Combinadas/administração & dosagemRESUMO
The purpose of this study was to estimate the apparent prevalence and identify risk factors for antibody levels (AL) against canine distemper virus (CDV), canine parvovirus (CPV), and canine adenovirus (CAV) in three communities in the metropolitan area of Quito, Ecuador that have limited access to regular veterinary care. Whole blood samples were collected from 154 dogs presenting to three veterinary field clinics in mainland Ecuador and tested for AL against CDV, CPV, and CAV by a commercially available point-of-care ELISA. Potential risk factors for the presence of AL were analyzed. A majority of dogs had AL against CDV (66%, 95% CIâ¯=â¯58-73%), CPV (95%, 95% CIâ¯=â¯91-98%) and CAV (60%, 95% CIâ¯=â¯52-67%). Dogs had significantly greater odds of AL against CDV if they were >2 years of age, from an urban community, and had previously received veterinary care. Dogs had significantly greater odds of AL against CAV if they were male, >2 years of age, and had previously received veterinary care. Results provide baseline estimates of AL within each community and allow for the targeting of future veterinary services to communities and dogs most at risk.
Assuntos
Adenovirus Caninos/imunologia , Anticorpos Antivirais/sangue , Vírus da Cinomose Canina/imunologia , Cinomose/epidemiologia , Doenças do Cão/epidemiologia , Parvovirus Canino/imunologia , Fatores Etários , Animais , Cinomose/imunologia , Doenças do Cão/imunologia , Doenças do Cão/virologia , Cães/imunologia , Equador/epidemiologia , Feminino , Masculino , Prevalência , Fatores de Risco , Reforma UrbanaRESUMO
Vaccination is a key element in the control of foot-and-mouth disease (FMD). The majority of the antigenic sites that induce protective immune responses are localized on the FMD virus (FMDV) capsid that is formed by four virus-encoded structural proteins, VP1 to VP4. In the present study, recombinant canine adenovirus type 2 (CAV2)-based FMD vaccines, Cav-P1/3C R° and Cav-VP1 R°, respectively expressing the structural P1 precursor protein along with the non-structural 3C protein or expressing the structural VP1 protein of the FMDV strain O/FRA/1/2001, were evaluated as novel vaccines against FMD. A strong humoral immune response was elicited in guinea pigs (GP) following immunization with Cav-P1/3C R°, while administration of Cav-VP1 R° did not induce a satisfying antibody response in GP or mice. GP were then used as an experimental model for the determination of the protection afforded by the Cav-P1/3C R° vaccine against challenge with the FMDV strain O1 Manisa/Turkey/1969. The Cav-P1/3C R° vaccine protected GP from generalized FMD to a similar extent as a high potency double-oil emulsion O1 Manisa vaccine. The results of the present study show that CAV2-based vector vaccines can express immunogenic FMDV antigens and offer protection against generalized FMD in GP. This suggest that Cav-P1/3C R° FMDV vaccine may protect natural host species from FMD. In combination with an appropriate diagnostic test, the Cav-P1/3C R° FMDV vaccine may also serve as a marker vaccine to differentiate vaccinated from infected animals.
Assuntos
Adenovirus Caninos/genética , Adenovirus Caninos/imunologia , Reações Cruzadas/imunologia , Vírus da Febre Aftosa/imunologia , Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Cães , Feminino , Cobaias , Imunização , Imunogenicidade da Vacina , Masculino , Camundongos , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologiaRESUMO
OBJECTIVES: To determine the utility of an in-practice test kit to detect protective serum antibody against canine distemper virus, canine adenovirus and canine parvovirus type 2 in a sample of the UK dog population. MATERIALS AND METHODS: Serum samples from 486 dogs, last vaccinated between less than 1 month and 124 months previously, were tested with the VacciCheck™ test kit for protective antibodies against distemper, adenovirus and parvovirus type 2. RESULTS: A high proportion of the dogs tested (93·6%) had protective antibody against all three of the core vaccine antigens: 95·7% of the dogs were seropositive against canine distemper virus, 97·3% against canine adenovirus and 98·5% against canine parvovirus type 2. The small number of dogs that were seronegative for one or more of the antigens (n = 31) may have had waning of previous serum antibody or may have been rare genetic non-responders to that specific antigen. CLINICAL SIGNIFICANCE: UK veterinarians can be reassured that triennial revaccination of adult dogs with core vaccines provides long-lived protective immunity. In-practice serological test kits are a valuable tool for informing decision-making about canine core revaccination.
Assuntos
Infecções por Adenoviridae/veterinária , Anticorpos Antivirais/sangue , Cinomose/imunologia , Doenças do Cão/imunologia , Infecções por Parvoviridae/veterinária , Vacinação/veterinária , Infecções por Adenoviridae/imunologia , Adenovirus Caninos/imunologia , Animais , Vírus da Cinomose Canina/imunologia , Doenças do Cão/virologia , Cães , Feminino , Masculino , Infecções por Parvoviridae/imunologia , Parvovirus Canino/imunologia , Reino Unido , Vacinas ViraisRESUMO
The assessment of vaccine combinations, or the evaluation of the impact of minor modifications of one component in well-established vaccines, requires animal challenges in the absence of previously validated correlates of protection. As an alternative, we propose conducting a multivariate analysis of the specific immune response to the vaccine. This approach is consistent with the principles of the 3Rs (Refinement, Reduction and Replacement) and avoids repeating efficacy studies based on infectious challenges in vivo. To validate this approach, a set of nine immunological parameters was selected in order to characterize B and T lymphocyte responses against canine rabies virus and to evaluate the compatibility between two canine vaccines, an inactivated rabies vaccine (RABISIN®) and a combined vaccine (EURICAN® DAPPi-Lmulti) injected at two different sites in the same animals. The analysis was focused on the magnitude and quality of the immune response. The multi-dimensional picture given by this 'immune fingerprint' was used to assess the impact of the concomitant injection of the combined vaccine on the immunogenicity of the rabies vaccine. A principal component analysis fully discriminated the control group from the groups vaccinated with RABISIN® alone or RABISIN®+EURICAN® DAPPi-Lmulti and confirmed the compatibility between the rabies vaccines. This study suggests that determining the immune fingerprint, combined with a multivariate statistical analysis, is a promising approach to characterizing the immunogenicity of a vaccine with an established record of efficacy. It may also avoid the need to repeat efficacy studies involving challenge infection in case of minor modifications of the vaccine or for compatibility studies.
Assuntos
Vacinas/imunologia , Adenovirus Caninos/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Antígenos Virais/imunologia , Vírus da Cinomose Canina/imunologia , Doenças do Cão/imunologia , Doenças do Cão/prevenção & controle , Doenças do Cão/virologia , Cães , Feminino , Imunidade/imunologia , Leptospira/imunologia , Masculino , Análise Multivariada , Parvovirus Canino/imunologia , Raiva/imunologia , Raiva/prevenção & controle , Raiva/veterinária , Vacina Antirrábica/imunologia , Vacina Antirrábica/uso terapêutico , Vírus da Raiva/imunologia , Respirovirus/imunologia , Resultado do Tratamento , Vacinas/uso terapêutico , Vacinas Combinadas/imunologia , Vacinas Combinadas/uso terapêuticoRESUMO
Raccoons (Procyon lotor) are found worldwide. They are frequently seen in crowded inner cities as well as in forests or wooded areas, often living in proximity to humans and their pets. We examined sera from 100 wild raccoons in Japan for antibodies to six canine viruses with veterinary significance to assess their potential as reservoirs. We also aimed to understand the distribution of potentially infected wildlife. We found that 7% of samples were seropositive for canine distemper virus (CDV), 10% for canine parvovirus type 2, 2% for canine adenovirus type 1, 6% for canine adenovirus type 2, and 7% for canine coronavirus. No samples were found to be seropositive for canine parainfluenza virus. Seropositivity rates for canine distemper virus and canine parvovirus type 2 were significantly different between areas, and younger raccoons (<1 yr old) were more frequently seropositive than older raccoons. Because raccoons belong to the suborder Caniformia, similar to dogs (Canis lupus familiaris), our results suggest that they can act as reservoirs for some of these important canine viruses and might be involved in viral transmission. Further study should include isolation and analysis of canine viruses in wild raccoons from a wider area.
Assuntos
Anticorpos Antivirais/sangue , Guaxinins/virologia , Viroses/veterinária , Adenovirus Caninos/classificação , Adenovirus Caninos/imunologia , Distribuição por Idade , Animais , Animais Selvagens , Gatos , Linhagem Celular , Chlorocebus aethiops , Coronavirus Canino/imunologia , Vírus da Cinomose Canina/imunologia , Feminino , Japão/epidemiologia , Masculino , Paramyxoviridae/imunologia , Infecções por Paramyxoviridae/epidemiologia , Infecções por Paramyxoviridae/imunologia , Infecções por Paramyxoviridae/veterinária , Infecções por Paramyxoviridae/virologia , Parvovirus Canino/imunologia , Estudos Soroepidemiológicos , Células Vero , Viroses/epidemiologia , Viroses/imunologiaRESUMO
Canine adenovirus type 1 (CAV-1) causes infectious canine hepatitis (ICH), a frequently fatal disease which primarily affects canids. In this study, serology (ELISA) and molecular techniques (PCR/qPCR) were utilised to investigate the exposure of free-ranging red foxes (Vulpes vulpes) to CAV-1 in the United Kingdom (UK) and to examine their role as a wildlife reservoir of infection for susceptible species. The role of canine adenovirus type 2 (CAV-2), primarily a respiratory pathogen, was also explored. In foxes with no evidence of ICH on post-mortem examination, 29 of 154 (18.8%) red foxes had inapparent infections with CAV-1, as detected by a nested PCR, in a range of samples, including liver, kidney, spleen, brain, and lung. CAV-1 was detected in the urine of three red foxes with inapparent infections. It was estimated that 302 of 469 (64.4%) red foxes were seropositive for canine adenovirus (CAV) by ELISA. CAV-2 was not detected by PCR in any red foxes examined. Additional sequence data were obtained from CAV-1 positive samples, revealing regional variations in CAV-1 sequences. It is concluded that CAV-1 is endemic in free-ranging red foxes in the UK and that many foxes have inapparent infections in a range of tissues.
Assuntos
Infecções por Adenoviridae/patologia , Adenovirus Caninos/genética , Raposas/virologia , Infecções por Adenoviridae/epidemiologia , Infecções por Adenoviridae/veterinária , Infecções por Adenoviridae/virologia , Adenovirus Caninos/imunologia , Adenovirus Caninos/isolamento & purificação , Animais , Anticorpos Antivirais/sangue , DNA Viral/química , DNA Viral/metabolismo , Ensaio de Imunoadsorção Enzimática , Hepatite Animal/epidemiologia , Hepatite Animal/patologia , Hepatite Animal/virologia , Prevalência , Análise de Sequência de DNA , Reino Unido/epidemiologia , Carga ViralRESUMO
Canine adenoviruses are a major cause of disease in dogs, coyotes, red foxes and wolves, as well as in other carnivores and marine mammals. Canine adenovirus type 1 (CAdV-1) and canine adenovirus type 2 (CAdV-2) cause infectious canine hepatitis (ICH) and infectious tracheobronchitis (ITB), respectively. In this study, a duplex real-time PCR assay for simultaneous detection and characterisation of CAdV-1 and CAdV-2 was developed by using a single primer pair and virus-specific probes. The assay was validated testing standard DNAs produced on purpose and clinical samples of various matrices known to be positive for CAdV-1, CAdV-2 or both viruses. Precise calculation of DNA loads in samples containing a wide range of viral amounts was allowed by generating a standard curve for absolute quantification. The assay was proven to be highly specific, since no cross-reactions with the different CAdV type was observed, and sensitive, being able to detect less than 10 copies of CAdV-1/CAdV-2 DNA. The low intra-assay and interassay coefficient of variations demonstrated a high repeatability, thus confirming the potential use of this assay for quantitative detection of CAdV-1 and CAdV-2 for rapid diagnosis and epidemiological investigations.
Assuntos
Adenovirus Caninos/isolamento & purificação , Hepatite Infecciosa Canina/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adenovirus Caninos/imunologia , Animais , Primers do DNA , Cães , Hepatite Infecciosa Canina/virologia , Sensibilidade e EspecificidadeRESUMO
Coyotes (Canis latrans) have expanded recently into the eastern US and can serve as a source of pathogens to domestic dogs (Canis lupus familiaris), livestock, and humans. We examined free-ranging coyotes from central North Carolina, US, for selected parasites and prevalence of antibodies against viral and bacterial agents. We detected ticks on most (81%) coyotes, with Amblyomma americanum detected on 83% of those with ticks. Fifteen (47%) coyotes were positive for heartworms (Dirofilaria immitis), with a greater detection rate in adults (75%) than juveniles (22%). Serology revealed antibodies against canine adenovirus (71%), canine coronavirus (32%), canine distemper virus (17%), canine parvovirus (96%), and Leptospira spp. (7%). We did not detect antibodies against Brucella abortus/suis or Brucella canis. Our results showed that coyotes harbor many common pathogens that present health risks to humans and domestic animals and suggest that continued monitoring of the coyote's role in pathogen transmission is warranted.
Assuntos
Coiotes/parasitologia , Infecções por Adenoviridae/imunologia , Infecções por Adenoviridae/veterinária , Adenovirus Caninos/imunologia , Fatores Etários , Animais , Animais Selvagens/sangue , Animais Selvagens/parasitologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/veterinária , Coronavirus Canino/imunologia , Coiotes/sangue , Coiotes/microbiologia , Coiotes/virologia , Dirofilaria , Dirofilariose/parasitologia , Cinomose/imunologia , Vírus da Cinomose Canina/imunologia , Feminino , Leptospira/imunologia , Leptospirose/imunologia , Leptospirose/veterinária , Masculino , North Carolina , Infecções por Parvoviridae/imunologia , Infecções por Parvoviridae/veterinária , Parvovirus Canino/imunologia , Testes Sorológicos/veterinária , Infestações por Carrapato/parasitologia , Infestações por Carrapato/veterinária , CarrapatosRESUMO
BACKGROUND: The use of recombinant viral vectors expressing T. gondii antigens is a safe and efficient approach to induce immune responses against the parasite, as well as a valuable tool for vaccine development. We have previously prolonged the survival time of mice challenged with the RH strain of T. gondii by immunizing the mice with a eukaryotic vector expressing the protein ROP18 of T. gondii. We are now looking for ways to improve this vaccination strategy and enhance protection. METHODS: In this study, we constructed and characterized a novel recombinant canine adenovirus type 2 expressing ROP18 (CAV-2-ROP18) of T. gondii by cytopathic effect (CPE) and indirect immunofluorescence assay (IFA) following transfection into MDCK cells. Intramuscular immunization of Kunming mice with CAV-2-ROP18 was carried out to evaluate humoral and cellular immune responses. RESULTS: The vaccination of experimental mice with CAV-2-ROP18 elicited antibody production against ROP18, including high levels of a mixed IgG1/IgG2a and significant production of IFN-γ or IL-2, and displayed a significant bias towards a helper T cell type 1 (Th1) profile. Furthermore, the presence of T. gondii-specific IFN-γ-production and TNF-α-production T cells was elicited in both CD4+ and CD8+ T cell compartments. Significantly higher survival rates (40%) occurred in the experimental group, and a reduction in brain cyst burden was detected in vaccinated mice. CONCLUSION: These results demonstrate the potential use of a CAV vector harboring the ROP18 gene in the development of a vaccine against acute and chronic toxoplasmosis.
Assuntos
Adenovirus Caninos/imunologia , Proteínas Serina-Treonina Quinases/imunologia , Vacinas Protozoárias , Toxoplasma/imunologia , Toxoplasmose Animal/prevenção & controle , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Linfócitos T CD8-Positivos/imunologia , Feminino , Imunidade Celular/imunologia , Injeções Intramusculares , Camundongos , Proteínas de Protozoários , Organismos Livres de Patógenos Específicos , Toxoplasmose Animal/imunologia , Vacinas de DNA/imunologiaRESUMO
There is an increasing concern that free-ranging domestic dog (Canis familiaris) populations may serve as reservoirs of pathogens which may be transmitted to wildlife. We documented the prevalence of antibodies to three viral pathogens, canine parvovirus (CPV), canine distemper virus (CDV) and canine adenovirus (CAV), in free-ranging dog and sympatric Indian fox (Vulpes bengalensis) populations in and around the Great Indian Bustard Wildlife Sanctuary, in Maharashtra, central India. A total of 219 dogs and 33 foxes were sampled during the study period. Ninety-three percentage of dogs and 87% of foxes were exposed to one or more of the three pathogens. Exposure rates in dogs were high: >88% for CPV, >72% for CDV and 71% for CAV. A large proportion of adult dogs had antibodies against these pathogens due to seroconversion following earlier natural infection. The high prevalence of exposure to these pathogens across the sampling sessions, significantly higher exposure rates of adults compared with juveniles, and seroconversion in some unvaccinated dogs documented during the study period suggests that these pathogens are enzootic. The prevalence of exposure to CPV, CDV and CAV in foxes was 48%, 18% and 52%, respectively. Further, a high rate of mortality was documented in foxes with serologic evidence of ongoing CDV infection. Dogs could be playing a role in the maintenance and transmission of these pathogens in the fox population, but our findings show that most dogs in the population are immune to these pathogens by virtue of earlier natural infection, and therefore, these individuals make little current or future contribution to viral maintenance. Vaccination of this cohort will neither greatly improve their collective immune status nor contribute to herd immunity. Our findings have potentially important implications for dog disease control programmes that propose using canine vaccination as a tool for conservation management of wild carnivore populations.
Assuntos
Adenovirus Caninos/imunologia , Vírus da Cinomose Canina/imunologia , Doenças do Cão/epidemiologia , Doenças do Cão/virologia , Raposas/virologia , Parvovirus Canino/imunologia , Adolescente , Fatores Etários , Animais , Anticorpos Antivirais , Cinomose/epidemiologia , Cães , Humanos , Índia/epidemiologia , Prevalência , Vacinação/veterináriaRESUMO
Ferret badgers (Melogale moschata) are a major reservoir of rabies virus in southeastern China. Oral immunization has been shown to be a practical method for wildlife rabies management in Europe and North America. Two groups of 20 ferret badgers were given a single oral dose of a recombinant canine adenovirus-rabies vaccine, CAV-2-E3Δ-RGP, or an experimental attenuated rabies virus vaccine, SRV9. At 21 days, all ferret badgers had seroconverted, with serum virus-neutralizing antibodies ranging from 0.1 to 4.5 IU/mL. Titers were >0.50 IU/mL (an acceptable level) in 17/20 and 16/20 animals receiving CAV-2-E3Δ-RGP or SRV9, respectively. The serologic results indicate that the recombinant CAV-2-E3Δ-RGP is at least as effective as the attenuated rabies virus vaccine. Both may be considered for additional research as oral rabies vaccine candidates for ferret badgers.
Assuntos
Infecções por Adenoviridae/veterinária , Adenovirus Caninos/imunologia , Mustelidae , Vírus da Raiva/imunologia , Raiva/veterinária , Vacinas Virais/imunologia , Infecções por Adenoviridae/prevenção & controle , Administração Oral , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Reservatórios de Doenças , Raiva/epidemiologia , Raiva/prevenção & controle , Vacinas AtenuadasRESUMO
Rabies in dogs can be controlled through mass vaccination. Oral vaccination of domestic dogs would be useful in the developing world, where greater vaccination coverage is needed especially in inaccessible areas or places with large numbers of free-roaming dogs. From this perspective, recent research has focused on development of new recombinant vaccines that can be administered orally in a bait to be used as adjunct for parenteral vaccination. One such candidate, a recombinant canine adenovirus type 2 vaccine expressing the rabies virus glycoprotein (CAV2-RG), is considered a promising option for dogs, given host specificity and safety. To assess the potential use of this vaccine in domestic dog populations, we investigated the prevalence of antibodies against canine adenovirus type 2 in South African dogs. Blood was collected from 241 dogs from the Gauteng and KwaZulu-Natal provinces. Sampled dogs had not previously been vaccinated against canine adenovirus type 1 (CAV1) or canine adenovirus type 2 (CAV2). Animals from both provinces had a high percentage of seropositivity (45% and 62%), suggesting that CAV2 circulates extensively among domestic dog populations in South Africa. Given this finding, we evaluated the effect of pre-existing CAV-specific antibodies on the efficacy of the CAV2-RG vaccine delivered via the oral route in dogs. Purpose-bred Beagle dogs, which received prior vaccination against canine parvovirus, canine distemper virus and CAV, were immunized by oral administration of CAV2-RG. After rabies virus (RABV) infection all animals, except one vaccinated dog, developed rabies. This study demonstrated that pre-existing antibodies against CAV, such as naturally occurs in South African dogs, inhibits the development of neutralizing antibodies against RABV when immunized with a CAV-based rabies recombinant vaccine.
Assuntos
Adenovirus Caninos/imunologia , Anticorpos Antivirais/sangue , Doenças do Cão/prevenção & controle , Vacina Antirrábica/imunologia , Raiva/imunologia , Vacinas Sintéticas/imunologia , Adenovirus Caninos/genética , Administração Oral , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais/imunologia , Doenças do Cão/imunologia , Cães , Raiva/prevenção & controle , Raiva/veterinária , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/genética , Estudos Soroepidemiológicos , África do Sul , Resultado do Tratamento , Vacinas Sintéticas/administração & dosagemRESUMO
Canine hepacivirus (CHV) was recently identified in domestic dogs and horses. The finding that CHV is genetically the virus most closely related to hepatitis C virus (HCV) has raised the question of whether HCV might have evolved as the result of close contact between dogs and/or horses and humans. The aim of this study was to investigate whether the NS3/4A serine protease of CHV specifically cleaves human mitochondrial antiviral signaling protein (MAVS) and Toll-IL-1 receptor domain-containing adaptor inducing interferon-beta (TRIF). The proteolytic activity of CHV NS3/4A was evaluated using a bacteriophage lambda genetic screen. Human MAVS- and TRIF-specific cleavage sites were engineered into the lambda cI repressor. Upon infection of Escherichia coli cells coexpressing these repressors and a CHV NS3/4A construct, lambda phage replicated up to 2000-fold more efficiently than in cells expressing a CHV protease variant carrying the inactivating substitution S139A. Comparable results were obtained when several HCV NS3/4A constructs of genotype 1b were assayed. This indicates that CHV can disrupt the human innate antiviral defense signaling pathway and suggests a possible evolutionary relationship between CHV and HCV.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transporte Vesicular/química , Adenovirus Caninos/enzimologia , Proteólise , Serina Endopeptidases/química , Proteínas não Estruturais Virais/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/imunologia , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Adenovirus Caninos/genética , Adenovirus Caninos/imunologia , Animais , Cães , Hepacivirus/enzimologia , Hepacivirus/genética , Hepacivirus/imunologia , Hepacivirus/metabolismo , Humanos , Imunidade Inata/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Serina Endopeptidases/genética , Serina Endopeptidases/imunologia , Serina Endopeptidases/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/imunologia , Proteínas não Estruturais Virais/metabolismoRESUMO
Domesticated adult dogs with antibody titer classified as below 'high' to one or more of canine distemper virus (CDV), canine parvovirus type-2 (CPV-2) and canine adenovirus type-1 (CAdV-1) were then given an additional inoculation, and the effectiveness of this booster evaluated 2 months later. Consequently, CDV and CAdV-1 antibody titer experienced a significant increase, but the same effect was not observed in the antibody titer of CPV-2. These findings suggest that with additional inoculation, a booster effect may be expected in increasing antibody titers for CDV and CAdV-1, but it is unlikely to give an increase in CPV-2 antibody titer.
Assuntos
Adenovirus Caninos/imunologia , Vírus da Cinomose Canina/imunologia , Imunização Secundária , Parvovirus Canino/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Cães , Vacinas Combinadas/administração & dosagem , Vacinas Combinadas/imunologia , Vacinas Virais/administração & dosagemRESUMO
BACKGROUND: Peste des petits ruminants (PPR) is a highly contagious infectious disease of goats, sheep and small wild ruminant species with high morbidity and mortality rates. The Peste des petits ruminants virus (PPRV) expresses a hemagglutinin (H) glycoprotein on its outer envelope that is crucial for viral attachment to host cells and represents a key antigen for inducing the host immune response. METHODOLOGY/PRINCIPAL FINDINGS: To determine whether H can be exploited to generate an effective PPRV vaccine, a replication-competent recombinant canine adenovirus type-2 (CAV-2) expressing the H gene of PPRV (China/Tibet strain) was constructed by the in vitro ligation method. The H expression cassette, including the human cytomegalovirus (hCMV) promoter/enhancer and the BGH early mRNA polyadenylation signal, was inserted into the SspI site of the E3 region, which is not essential for proliferation of CAV-2. Infectious recombinant rCAV-2-PPRV-H virus was generated in transfected MDCK cells and used to immunize goats. All vaccinated animals produced antibodies upon primary injection that were effective in neutralizing PPRV in vitro. Higher antibody titer was obtained following booster inoculation, and the antibody was detectable in goats for at least seven months. No serious recombinant virus-related adverse effect was observed in immunized animals and no adenovirus could be isolated from the urine or feces of vaccinated animals. Results showed that the recombinant virus was safe and could stimulate a long-lasting immune response in goats. CONCLUSIONS/SIGNIFICANCE: This strategy not only provides an effective PPR vaccine candidate for goats but may be a valuable mean by which to differentiate infected from vaccinated animals (the so-called DIVA approach).
Assuntos
Adenovirus Caninos/imunologia , Doenças das Cabras/prevenção & controle , Doenças das Cabras/virologia , Peste dos Pequenos Ruminantes/veterinária , Vírus da Peste dos Pequenos Ruminantes/imunologia , Vacinas Virais/uso terapêutico , Adenovirus Caninos/genética , Análise de Variância , Animais , Anticorpos Antivirais/sangue , Western Blotting , Linhagem Celular , Primers do DNA/genética , Cães , Imunofluorescência , Cabras , Hemaglutininas Virais/genética , Hemaglutininas Virais/metabolismo , Técnicas In Vitro , Leucócitos Mononucleares/imunologia , Testes de Neutralização , Peste dos Pequenos Ruminantes/prevenção & controle , Vírus da Peste dos Pequenos Ruminantes/genética , Vacinas Sintéticas/genética , Vacinas Sintéticas/uso terapêutico , Vacinas Virais/genéticaRESUMO
The objective of this study was to determine whether post-vaccination antibody titers vary according to body weight in adult dogs. Antibody titers against canine parvovirus type 2 (CPV-2), canine distemper virus (CDV), and canine adenovirus type 1 (CAdV-1) were measured for 978 domestic adult dogs from 2 to 6 y of age. The dogs had been vaccinated approximately 12 mo earlier with a commercial combination vaccine. The dogs were divided into groups according to their weight. It was found that mean antibody titers in all weight groups were sufficient to prevent infection. Intergroup comparison, however, revealed that CPV-2 antibody titers were significantly higher in the Super Light (< 5 kg) group than in the Medium (10 to 19.9 kg) and Heavy (> 20 kg) groups and were also significantly higher in the Light (5 to 9.9 kg) group than in the Heavy group. Antibody titers against CDV were significantly higher in the Super Light, Light, and Medium groups than in the Heavy group. There were no significant differences among the groups for the CAdV-1 antibody titers.
Pour vérifier que les taux d'anticorps chez des chiens vaccinés changeaient en fonction de leur poids après la vaccination par un vaccin commercial combiné, on a mesuré les anticorps antivirus de la parvovirose canine (CPV-2), de la maladie de Carré (CDV) et de l'encéphalite de Rubarth type-1 (CAdV-1) chez 978 chiens de compagnie agés de 2 à 6 ans, un an après leur vaccination. Par nos mesures, nous observons dans tous les groupes un taux satisfaisant d' immunisation moyen des animaux. Mais en comparant les groupes de poids, on s'aperçoit que pour la parvovirose canine CPV-2, le groupe des super-légers (< 5 kg) est significativement plus protégé en anticorps que les groupes de poids moyen (de 10 à 19,9 kg) et de poids le plus lourd (> 20 kg). De même les poids légers (de 5 à 9,9 kg) sont significativement mieux protégés que les poids lourds. Pour la maladie de Carré (CDV), les super-légers, les poids légers ou les groupes de poids moyen ont un taux d'anticorps significativement plus élevé que les plus lourds. Par contre pour l'Encéphalite de Rubarth (CAdV-1) aucune différence des taux d'anticorps dans les groupes de poids n'a été observée.(Traduit par les auteurs).
Assuntos
Adenovirus Caninos/imunologia , Anticorpos Antivirais/sangue , Vírus da Cinomose Canina/imunologia , Doenças do Cão/virologia , Parvovirus Canino/imunologia , Vacinas Virais/imunologia , Animais , Peso Corporal/imunologia , Doenças do Cão/imunologia , Doenças do Cão/prevenção & controle , Cães , Feminino , Masculino , Estatísticas não Paramétricas , Vacinação/veterinária , Vacinas Virais/administração & dosagemRESUMO
Serum antibody titers for canine parvovirus type-2 (CPV-2), canine distemper virus (CDV) and canine adenovirus type-1 (CAV-1) were investigated in 1031 healthy adult household dogs (2 to 18 years old) given an annual inoculation in the previous 11 to 13 months. The number of dogs retaining significant titers of antibodies against CPV-2, CDV, and CAV-1 were 888 (86%), 744 (72%), and 732 (71%), respectively. There were no differences between males and females in antibody titers against the 3 viruses. Antibody titer for CPV-2 was significantly higher in younger dogs than in older dogs, CDV antibody was significantly higher in older dogs than in younger dogs, and CAV titer was not associated with age.