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1.
Rev Sci Tech ; 39(2): 543-550, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33046921

RESUMO

Veterinary vaccine banks, also referred to as vaccine stockpiles or vaccine strategic reserves, play an important role in the response to infectious animal diseases, by assisting control of the disease and resilience in recovering from its effects. Vaccine banks have a part to play in both emergencies and control programmes. The concept of vaccine banks was initially established as a countermeasure to an animal disease emergency or outbreak or the introduction of a new disease. They have increasingly been used to prevent important diseases identified by Veterinary Authorities as requiring a well-planned control programme through vaccination. Vaccine banks can consist of physical or virtual reserves, or the maintenance of production capacity. Physical reserves comprise vaccine antigen or readyto-use vaccines. Virtual reserves include inventory management by vaccine manufacturers. Maintenance of production capacity encompasses management of the vaccine seed material, and the maintenance of knowledge by the manufacturers through continued research into the target vaccines. The establishment, maintenance and implementation of vaccine banks depend on a number of prerequisites, which include a strategy for the physical or virtual vaccine stockpile, a legislative framework, regulatory arrangements, effective supply-chain mechanisms and adequate surveillance systems. Through international solidarity, vaccine banks are available and accessible to countries that do not have their own reserves. The World Organisation for Animal Health and European Union vaccine banks perform this task. Moreover, vaccine banks have facilitated access to important public health vaccines, such as rabies vaccines. These issues are discussed below, as well as potential opportunities for public-private partnerships in different aspects of vaccine banks.


Assuntos
Doenças dos Animais , Vacinas Antirrábicas , Doenças dos Animais/prevenção & controle , Animais , Surtos de Doenças , Saúde Global , Vacinação/veterinária
2.
J Vet Sci ; 21(5): e74, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016020

RESUMO

BACKGROUND: The quality of a vaccine depends strongly on the effects of the adjuvants applied simultaneously with the antigen in the vaccine. The adjuvants enhance the protective effect of the vaccine against a viral challenge. Conversely, oil-type adjuvants leave oil residue inside the bodies of the injected animals that can produce a local reaction in the muscle. The long-term immunogenicity of mice after vaccination was examined. ISA206 or ISA15 oil adjuvants maintained the best immunity, protective capability, and safety among the oil adjuvants in the experimental group. OBJECTIVES: This study screened the adjuvant composites aimed at enhancing foot-and-mouth disease (FMD) immunity. The C-type lectin or toll-like receptor (TLR) agonist showed the most improved protection rate. METHODS: Experimental vaccines were fabricated by mixing various known oil adjuvants and composites that can act as immunogenic adjuvants (gel, saponin, and other components) and examined the enhancement effect on the vaccine. RESULTS: The water in oil (W/O) and water in oil in water (W/O/W) adjuvants showed better immune effects than the oil in water (O/W) adjuvants, which have a small volume of oil component. The W/O type left the largest amount of oil residue, followed by W/O/W and O/W types. In the mouse model, intramuscular inoculation showed a better protection rate than subcutaneous inoculation. Moreover, the protective effect was particularly weak in the case of inoculation in fatty tissue. The initial immune reaction and persistence of long-term immunity were also confirmed in an immune reaction on pigs. CONCLUSIONS: The new experimental vaccine with immunostimulants produces improved immune responses and safety in pigs than general oil-adjuvanted vaccines.


Assuntos
Adjuvantes Imunológicos/farmacologia , Vírus da Febre Aftosa/imunologia , Febre Aftosa/prevenção & controle , Doenças dos Suínos/prevenção & controle , Vacinação/veterinária , Vacinas Virais/farmacologia , Animais , Anticorpos Antivirais/imunologia , Formação de Anticorpos , Febre Aftosa/imunologia , Febre Aftosa/virologia , Camundongos , Camundongos Endogâmicos C57BL , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Vacinas Virais/imunologia
3.
Poult Sci ; 99(9): 4351-4359, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32867979

RESUMO

The vaccines currently available to control infectious bursal disease (IBD) include live-attenuated and inactivated vaccines, immune-complex vaccines, and vaccines consisting of viral constructs of herpesvirus of turkeys genetically engineered to express VP2 surface protein. To evaluate the impact of vaccines on the chicken immune system, 2 animal trials were performed in specific pathogen-free broiler chickens. In trial 1, birds were either vaccinated when they are one-day old with a dual recombinant herpes virus of turkey construct vaccine, expressing VP2 protein of (IBDV) and F protein of Newcastle disease virus, or an immune-complex IBDV vaccine or birds were not vaccinated. At 14, 28, and 35 D, the bursa of Fabricius was collected for bursa:body weight (B:BW) ratio calculation. In trial 2, birds were vaccinated when they were 1-day old according to the same protocol as trial 1, but at day 14, all groups also received a live infectious bronchitis (IB) vaccine. At 0, 7, 14, 21, and 28 days after IB vaccination, birds were tested by ELISA for IB serology and, soon after the last blood sampling, they were euthanized for collection of Harderian glands, trachea, and spleen and testing by flow cytometry for characterization of mononuclear cells. The immune-complex vaccine groups showed significantly lower B:BW ratio, lower IBV antibody titers, and higher mean percentage of CD8+ T cells in the spleen, trachea, and Harderian glands than those in the other experimental groups. The results of the in vivo trials coupled with a depth analysis of the repertoire of parameters involved in the immune response to IBD and IB vaccinations show one vaccine may influence the immune response of other vaccines included in the vaccination program.


Assuntos
Infecções por Birnaviridae/veterinária , Doenças das Aves Domésticas/imunologia , Vacinas Virais/imunologia , Animais , Infecções por Birnaviridae/imunologia , Bolsa de Fabricius/patologia , Galinhas , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/imunologia , Vírus da Doença Infecciosa da Bursa/imunologia , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Organismos Livres de Patógenos Específicos , Vacinação/veterinária , Vacinas Atenuadas/imunologia
5.
Arch Virol ; 165(11): 2619-2625, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32770485

RESUMO

Foot-and-mouth disease virus (FMDV) serotype Asia1 is prevalent in India and is responsible for a minor proportion of FMD outbreaks. Globally, serotype Asia1 is grouped into nine different groups (GI-IX) based on genetic analysis. In India, only Asia1/G-III and Asia1/G-VIII have been documented so far. Phylogenetic analysis of recent serotype Asia1 isolates from India revealed the emergence of Asia1/G-IX. The Asia1/G-IX lineage shares recent common ancestry with Asia1/G-VIII dating to 2016. The root state posterior probabilities of Asia1/G-VIII are inclusive and there may have been either an incursion of the virus from Bangladesh, where it was first identified, or in situ evolution of the virus within India, which is an intriguing possibility.


Assuntos
Surtos de Doenças/veterinária , Vírus da Febre Aftosa/classificação , Febre Aftosa/epidemiologia , Substituição de Aminoácidos , Animais , Bangladesh , Teorema de Bayes , Proteínas do Capsídeo/genética , Febre Aftosa/virologia , Vírus da Febre Aftosa/isolamento & purificação , Índia/epidemiologia , Filogenia , Sorogrupo , Vacinação/veterinária
6.
Arch Virol ; 165(11): 2675-2677, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32772251

RESUMO

An uncharacteristic outbreak of lumpy skin disease was reported in the Republic of Udmurtiya, Russia, during the climatic winter of March 2019. The causative lumpy skin disease virus (LSDV_Udmurtiya_Russia_2019) was shown to be a recombinant composed of a live attenuated Neethling-type vaccine strain as the dominant parental strain and a Kenyan KSGP/NI-2490-like virus as its minor parental strain, with 24 statistically significant recombination events that are not identical to those in LSDV Saratov/2017, in which 27 events were identified.


Assuntos
Surtos de Doenças/veterinária , Doença Nodular Cutânea/epidemiologia , Vírus da Doença Nodular Cutânea/isolamento & purificação , Animais , Bovinos , DNA Viral/genética , Vírus da Doença Nodular Cutânea/genética , Reação em Cadeia da Polimerase , Federação Russa/epidemiologia , Estações do Ano , Vacinação/veterinária , Vacinas Atenuadas/imunologia
8.
Vet J ; 262: 105504, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32792093

RESUMO

Lyme disease (LD) is a tick-transmitted disease caused by Borreliella burgdorferi (Bb). Temporal studies of maternal antibody (Ab) profiles in Bb infected pregnant dogs and their pups have not been conducted. In this study, Ab profiles of a client-owned Bb C6 Ab positive Rottweiler and her nine pups were assessed. The dam presented with lameness 12 days prior to parturition and was C6 Ab positive with a Quant C6 Ab concentration of 237U/mL. Treatment with amoxicillin was initiated and 11 days later nine pups were delivered. Screening of the sera from the dam and pups against Bb cell lysates and a panel of antigens revealed similar immunoreactivity profiles. While antigen-specific IgG and IgM reactivity persisted in the dam for at least 7 months, a rapid decline in IgG specific for BBA36, BBK53, BB0238, BBA73 and outer surface protein (Osp) E in the pups occurred between days 29 and 52 post-parturition. In contrast, Ab specific for DbpA and the diagnostic antigens VlsE (C6) and OspF, remained elevated in the pups. Sera from the dam displayed potent complement-dependent bactericidal activity against Bb. Sera from the pups was also bactericidal but primarily through a complement-independent mechanism. Lastly, single dose vaccination of the dam at day 51 post-parturition with a LD subunit vaccine consisting of OspA and an OspC chimeritope triggered a broad anti-OspC Ab response indicative of an anamnestic response. Although this study focused on a single case, these findings add to our knowledge of maternal Ab profiles and will aid the interpretation of serological assays in pups delivered by a Bb C6 Ab positive dog.


Assuntos
Borrelia burgdorferi/imunologia , Doenças do Cão/diagnóstico , Vacinas contra Doença de Lyme/imunologia , Doença de Lyme/veterinária , Animais , Anticorpos Antibacterianos/sangue , Doenças do Cão/tratamento farmacológico , Doenças do Cão/imunologia , Cães , Feminino , Doença de Lyme/diagnóstico , Doença de Lyme/imunologia , Ontário , Vacinação/veterinária
9.
J S Afr Vet Assoc ; 91(0): e1-e6, 2020 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-32787425

RESUMO

Bovine brucellosis affects food safety, food security and human health in rural communities in the North West Province, South Africa. The World Organisation for Animal Health suggests routine sero-surveillance and vaccination of cattle for control and to prevent zoonotic transmission. Although sero-surveillance and subsidised vaccination have been in place for decades, data from Bojanala have not previously been analysed. The aim of this study was to retrospectively analyse historical data on routine sero-surveillance of bovine brucellosis and state subsidised vaccination, in communal, commercial and dairy cattle in the study area. This was a descriptive, cross-sectional retrospective analysis of records from all adult cows bled by the state veterinary services during routine sero-surveillance for bovine brucellosis, in the Bojanala Region, North West Province, between 2009 and 2013. Fewer communal (N = 11 815) and dairy (N = 6696), than commercial beef (N = 28 251) cows, were tested. Overall herd prevalence (33.33%), differed significantly from individual prevalence (3.18%) in all groups. Communal herds had both the highest herd prevalence (38.8%) and the highest individual prevalence (5.2%). Both herd and individual sero-prevalence were lowest in dairy cattle, possibly because registered dairy herds are routinely tested. Over the 5-year study period, only 24 086 (7.15%) of the 342 500 cows eligible for free vaccination, were vaccinated. The annual number of cattle tested was highly variable. Dairy cattle that were regularly tested had a significantly lower herd and individual prevalence. Herd prevalence would be useful for spatial mapping, whilst individual prevalence could better reflect the risk of zoonotic transmission.


Assuntos
Brucelose Bovina/epidemiologia , Vacinação/veterinária , Animais , Bovinos , Estudos Transversais , Feminino , Prevalência , Estudos Retrospectivos , Fatores de Risco , Estudos Soroepidemiológicos , África do Sul/epidemiologia
10.
Exp Parasitol ; 216: 107945, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32615133

RESUMO

Despite decades of investigation to clarify protective mechanisms of anticoccidial responses, one crucial field is neglected, that is, protective memory responses in primed birds. Protective memory immunity is critical for host resistance to reinfection and is the basis of modern vaccinology, especially in developing successful subunit vaccines. There are important differences between the immune responses induced by infections and antigens delivered either as killed, recombinant proteins or as live, replicating vector vaccines or as DNA vaccines. Animals immunized with these vaccines may fail to develop protective memory immunity, and is still naïve to Eimeria infection. This may explain why limited success is achieved in developing next-generation anticoccidial vaccines. In this review, we try to decipher the protective memory responses against Eimeria infection, assess immune responses elicited by various anticoccidial vaccine candidates, and propose possible approaches to develop rational vaccines that can induce a protective memory response to chicken coccidiosis.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria/imunologia , Memória Imunológica/fisiologia , Doenças das Aves Domésticas/imunologia , Vacinas Protozoárias , Animais , Galinhas/imunologia , Coccidiose/imunologia , Coccidiose/prevenção & controle , Intestinos/imunologia , Intestinos/parasitologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/imunologia , Recidiva , Vacinação/veterinária , Vacinas de Subunidades/imunologia
11.
Viruses ; 12(7)2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32674326

RESUMO

The Gammacoronavirus infectious bronchitis virus (IBV) is a highly contagious economically important respiratory pathogen of domestic fowl. Reverse genetics allows for the molecular study of pathogenic determinants to enable rational vaccine design. The recombinant IBV (rIBV) Beau-R, a molecular clone of the apathogenic Beaudette strain, has previously been investigated as a vaccine platform. To determine tissues in which Beau-R could effectively deliver antigenic genes, an in vivo study in chickens, the natural host, was used to compare the pattern of viral dissemination of Beau-R to the pathogenic strain M41-CK. Replication of Beau-R was found to be restricted to soft tissue within the beak, whereas M41-CK was detected in beak tissue, trachea and eyelid up to seven days post infection. In vitro assays further identified that, unlike M41-CK, Beau-R could not replicate at 41 °C, the core body temperature of a chicken, but is able to replicate a 37 °C, a temperature relatable to the very upper respiratory tract. Using a panel of rIBVs with defined mutations in the structural and accessory genes, viral replication at permissive and non-permissive temperatures was investigated, identifying that the Beau-R replicase gene was a determinant of temperature sensitivity and that sub-genomic mRNA synthesis had been affected. The identification of temperature sensitive allelic lesions within the Beau-R replicase gene opens up the possibility of using this method of attenuation in other IBV strains for future vaccine development as well as a method to investigate the functions of the IBV replicase proteins.


Assuntos
Infecções por Coronavirus/prevenção & controle , Vírus da Bronquite Infecciosa/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Linhagem Celular , Embrião de Galinha , Galinhas , Aves Domésticas/virologia , Doenças das Aves Domésticas/virologia , RNA Viral/genética , Temperatura , Vacinas Atenuadas/imunologia , Replicação Viral/genética , Replicação Viral/fisiologia
12.
PLoS One ; 15(7): e0236127, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32692783

RESUMO

Visceral leishmaniasis (VL) is an important zoonosis in Brazil. Dogs are considered the main domestic reservoirs of the disease in the country; hence, control measures are focused on these reservoirs. Despite efforts to prevent and control VL, important reductions in disease prevalence and incidence have not been identified, stimulating the development and application of new strategies. The choice and implementation of new control strategies can benefit from the application of mathematical models that allow the simulation of different strategies in different scenarios. Selecting the best strategy to be implemented is also supported by cost-effectiveness studies. Here we used the results of a mathematical model in which scenarios, including isolated use of the vaccine and insecticide-impregnated collar (IIC), both at different coverage rates, were simulated to conduct a cost-effectiveness study. The costs were calculated for each scenario considering a simulation period of four years. Collar application in both infected and non-infected animals was the most cost-effective strategy. For example, to reduce the prevalence in humans and dogs by approximately 70%, the costs ranged from $250,000 and $550,000 for the IICs and vaccination, respectively. Even in the scenario with 40% loss/replacement of IICs, this measure was more advantageous in terms of cost-effectiveness than vaccination. If the vaccine were applied with culling of seropositive tested dogs, then the measure became more effective with a reduced cost compared with the vaccine alone. The use of the three first consecutive vaccine doses had the greatest impact on the cost of the vaccination strategy. The advantage of using IICs is that there is no need for a prior diagnosis, unlike vaccination, reducing costs and facilitating implementation. The present study aims to contribute to strategies to reduce hosts infected with VL by reducing public expenditure.


Assuntos
Doenças do Cão/economia , Doenças do Cão/prevenção & controle , Leishmania donovani/efeitos dos fármacos , Leishmaniose Visceral/economia , Leishmaniose Visceral/prevenção & controle , Vacinação/economia , Vacinação/veterinária , Animais , Brasil/epidemiologia , Doenças do Cão/parasitologia , Doenças do Cão/transmissão , Cães , Leishmania donovani/isolamento & purificação , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/veterinária , Prevalência
13.
Parasitol Res ; 119(9): 2885-2895, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32715344

RESUMO

Chicken coccidiosis is a protozoan parasitic disease that leads to considerable economic losses in the poultry industry. In this study, we used invasive Lactobacillus plantarum (L.P) expressing the FnBPA protein as a novel bacterial carrier for DNA delivery into epithelial cells to develop a live oral DNA vaccine. A fusion DNA vaccine co-expressing EtMIC2 and chicken IL-18 (chIL-18) was constructed and then delivered to the host by invasive L.P. Its efficacy against Eimeria tenella challenge was evaluated in chickens by examining the relative weight gain rate; caecal lesion score; OPG; anti-coccidial index (ACI); levels of EtMIC2 antibody, FnBPA, IL-4, IL-18, IFN-γ and SIgA; and proliferation ability and percentages of CD4+ and CD8+ splenocytes. The experimental results showed that chickens immunized with invasive L.P carrying the eukaryotic expression vector pValac-EtMIC2 (pValac-EtMIC2/pSIP409-FnBPA) had markedly improved immune protection against challenge compared with that of chickens immunized with non-invasive L.P (pValac-EtMIC2/pSIP409). However, invasive L.P co-expressing EtMIC2 with the chIL-18 vector exhibited the highest protection efficiency against E. tenella. These results indicate that invasive Lactobacillus-expressing FnBPA improved humoural and cellular immunity and enhanced resistance to E. tenella. The DNA vaccine delivered by invasive Lactobacillus provides a new concept and method for the prevention of E. tenella.


Assuntos
Antígeno 12E7/metabolismo , Coccidiose/veterinária , Eimeria tenella/imunologia , Interleucina-18/metabolismo , Lactobacillus plantarum/metabolismo , Vacinas Protozoárias/imunologia , Vacinas de DNA/imunologia , Animais , Ceco/parasitologia , Galinhas/parasitologia , Coccidiose/parasitologia , Eimeria tenella/genética , Imunidade Celular/imunologia , Imunoglobulina A Secretora/genética , Lactobacillus plantarum/genética , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária , Ganho de Peso
14.
J Small Anim Pract ; 61(8): 487-493, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32715488

RESUMO

OBJECTIVE: To report PCR results and vaccination status of rabbits with rabbit haemorrhagic disease following an investigation into sudden or unexpected death. MATERIALS AND METHODS: PCR testing for RHDV2 and RHDV1 was performed on rabbit liver samples at two laboratories. Laboratory A reported results as positive or negative; Laboratory B reported results quantitatively as RNA copies per mg liver, categorised as negative, inconclusive or positive. The vaccination status of rabbits with both histopathological features of rabbit haemorrhagic disease and positive PCR test results were collated. RESULTS: PCR results matched histopathological findings in 188 of 195 (96%) cases. Seven individuals showed equivocal results, all of which had histopathological features of RHD but three tested PCR-negative and four results conflicted between laboratories. RHDV2 was the serotype detected in all PCR-positive cases. Histological features of rabbit haemorrhagic disease and PCR test results were positive in 125 rabbits; 51 unvaccinated, 56 in-date with Nobivac Myxo-RHD and 13 vaccinated against RHDV2 - although nine of these were vaccinated within 10 days of death. CLINICAL SIGNIFICANCE: PCR testing complements histopathology in cases of sudden death in rabbits by confirming the diagnosis and identifying virus serotype, but there can be false negatives. Although RHDV2 is currently prevalent in UK pet rabbits, vaccination against both RHDV1 and RHDV2 is recommended. Failures of RHDV2 vaccine are infrequent.


Assuntos
Infecções por Caliciviridae/veterinária , Vírus da Doença Hemorrágica de Coelhos/genética , Animais , Reação em Cadeia da Polimerase/veterinária , Coelhos , Reino Unido , Vacinação/veterinária
15.
Trop Anim Health Prod ; 52(6): 2809-2816, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32681447

RESUMO

Bovine coronaviruses are spread all over the world. They cause two types of clinical manifestations in cattle either an enteric, calf diarrhoea and winter dysentery in adult cattle, or respiratory in all age groups of cattle. The role of coronaviruses in respiratory infections is still a hot topic of discussion since they have been isolated from sick as well as healthy animals and replication of disease is rarely successful. Bovine coronavirus infection is characterised by high morbidity but low mortality. The laboratory diagnosis is typically based on serological or molecular methods. There is no registered drug for the treatment of virus infections in cattle and we are limited to supportive therapy and preventative measures. The prevention of infection is based on vaccination, biosecurity, management and hygiene. This paper will cover epidemiology, taxonomy, pathogenesis, clinical signs, diagnosis, therapy, economic impact and prevention of coronavirus infections in cattle.


Assuntos
Doenças dos Bovinos/virologia , Infecções por Coronavirus/veterinária , Coronavirus Bovino , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/terapia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Coronavirus Bovino/classificação , Coronavirus Bovino/isolamento & purificação , Coronavirus Bovino/fisiologia , Diarreia/veterinária , Diarreia/virologia , Enterocolite Necrosante/veterinária , Enterocolite Necrosante/virologia , Infecções Respiratórias/veterinária , Infecções Respiratórias/virologia , Vacinação/veterinária
16.
J Vet Diagn Invest ; 32(4): 598-603, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32560597

RESUMO

A 61-d-old fennec fox (Vulpes zerda), 11 d after receiving a multivalent, modified-live virus vaccine containing canine distemper virus (CDV), canine adenovirus 2 (CAdV-2), parainfluenza virus, parvovirus, and canine coronavirus, developed oculonasal discharge, and subsequently convulsions, and hemoptysis, and died. Microscopic changes in the cerebrum were evident, including neuronal degeneration and necrosis; intracytoplasmic eosinophilic inclusion bodies were observed in astrocytes. CDV was detected in the brain tissue by immunohistochemistry. Pulmonary lesions of multifocal necrotizing bronchopneumonia had Cowdry type A intranuclear inclusions in the bronchial epithelial cells. Electron microscopy revealed crystalline arrays of adenovirus-like particles within the intranuclear inclusions. Additionally, the hemagglutinin gene of CDV and the CAdV-2 DNA polymerase gene were detected in the fennec fox; sequence analysis showed 100% identity with those of the vaccine strain viruses. To our knowledge, vaccine-induced CDV and CAdV-2 coinfections using molecular analysis have not been reported previously. Therefore, vaccine strains should be considered prior to CDV vaccination in nondomestic carnivores.


Assuntos
Infecções por Adenoviridae/veterinária , Adenovirus Caninos/isolamento & purificação , Coinfecção/veterinária , Vírus da Cinomose Canina/isolamento & purificação , Raposas/virologia , Infecções por Adenoviridae/virologia , Animais , Encéfalo/virologia , Cinomose/virologia , Vírus da Cinomose Canina/genética , Evolução Fatal , Infecções por Parvoviridae/veterinária , Infecções por Parvoviridae/virologia , Vacinação/veterinária , Vacinas Atenuadas , Vacinas Virais/imunologia
17.
Virol J ; 17(1): 77, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32552831

RESUMO

BACKGROUND: Middle East Respiratory Syndrome coronavirus (MERS-CoV) is an emerging virus that infects humans and camels with no approved antiviral therapy or vaccine. Some vaccines are in development for camels as a one-health intervention where vaccinating camels is proposed to reduce human viral exposure. This intervention will require an understanding of the prior exposure of camels to the virus and appropriate vaccine efficacy studies in camels. METHODS: We conducted a cross sectional seroprevalence study in young dromedary camels to determine the rate of MERS-CoV seropositivity in young camels. Next, we utilised naturally infected camels as a natural challenge model that can be used by co-housing these camels with healthy naive camels in a ratio of 1 to 2. This model is aimed to support studies on natural virus transmission as well as evaluating drug and vaccine efficacy. RESULTS: We found that 90% of the screened camels have pre-existing antibodies for MERS-CoV. In addition, the challenge model resulted in MERS-CoV transmission within 48 h with infections that continued for 14 days post challenge. CONCLUSIONS: Our finding suggests that the majority of young dromedary camels in Saudi Arabia are seropositive and that naturally infected camels can serve as a challenge model to assess transmission, therapeutics, and vaccine efficacy.


Assuntos
Camelus/virologia , Infecções por Coronavirus/veterinária , Modelos Animais de Doenças , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Animais , Anticorpos Antivirais/sangue , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Estudos Transversais , Arábia Saudita/epidemiologia , Estudos Soroepidemiológicos , Vacinação/veterinária
18.
Avian Dis ; 64(2): 157-165, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32550616

RESUMO

The reemergence of infectious coryza (IC) caused by Avibacterium paragallinarum (AP) as an acute and occasionally chronic respiratory disease in domestic poultry has caused severe losses in several U.S. states. The disease is also associated with decreased egg production in layers and increased condemnations from air sac infections in broilers. A series of applied experiments were performed to elucidate the persistence of AP in infected broiler flocks, to genotype AP strains isolated from field cases, and to evaluate commercial and autogenous vaccine protection in commercial and specific-pathogen-free (SPF) chickens. Experimental evaluation of environmental persistence suggests that AP did not persist more than 12 hr in a hypothetically contaminated environment. Additionally, other detected potential pathogens such as Gallibacterium anatis and infectious bronchitis virus caused mild respiratory signs in the exposed birds. The HMTp210 and HagA genes of four IC field strains were sequenced and compared with published sequences of HMTp210 and HagA. The HMTp210 phylogeny showed a marginally imperfect clustering of the sequences in genogroups A, B, and C. Although not definitive, this phylogeny provided evidence that the four field strains aligned with previously characterized serovar C strains. Moreover, the base pair homology of the four strains was 100% identical to serovar C reference strains (H-18 and Modesto). HagA phylogeny was unclear, but interestingly, the IC field strains were 100% homologous to C-1 strains reported from Mexico and Ecuador. Finally, vaccine protection studies in commercial hens indicate that clinical signs are induced by a combination of IC and other concomitant pathogens infecting commercial birds. Additionally, vaccine protection experiments performed in SPF hens indicated that protection provided by the two commercial vaccines tested provided a reduction in clinical signs and bacterial shedding after two applications.


Assuntos
Vacinas Bacterianas/administração & dosagem , Galinhas , Genótipo , Infecções por Haemophilus/veterinária , Haemophilus paragallinarum/fisiologia , Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária , Animais , Feminino , Infecções por Haemophilus/microbiologia , Infecções por Haemophilus/prevenção & controle , Haemophilus paragallinarum/imunologia , Doenças das Aves Domésticas/microbiologia , Organismos Livres de Patógenos Específicos
19.
Vaccine ; 38(33): 5123-5130, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32563608

RESUMO

The current pandemic of COVID-19 has set off an urgent search for an effective vaccine. This search may well benefit from the experiences of the animal health profession in the development and use of coronavirus vaccines in domestic animal species. These animal vaccines will in no way protect humans against COVID-19 but knowledge of the difficulties encountered in vaccinating animals may help avoid or minimize similar problems arising in humans. Diverse coronaviruses can infect the domestic species from dogs and cats, to cattle and pigs to poultry. Many of these infections are controlled by routine vaccination. Thus, canine coronavirus vaccines are protective in puppies but the disease itself is mild and self-limiting. Feline coronavirus infections may be mild or may result in a lethal immune-mediated disease - feline infectious peritonitis. As a result, vaccination of domestic cats must seek to generate- protective immunity without causing immune-mediated disease. Vaccines against bovine coronavirus are widely employed in cattle where they protect against enteric and respiratory disease in young calves. Two major livestock species suffer from economically significant and severe coronavirus diseases. Thus, pigs may be infected with six different coronaviruses, one of which, porcine epidemic diarrhea, has proven difficult to control despite the development of several innovative vaccines. Porcine epidemic diarrhea virus undergoes frequent genetic changes. Likewise, infectious bronchitis coronavirus causes an economically devastating disease of chickens. It too undergoes frequent genetic shifts and as a result, can only be controlled by extensive and repeated vaccination. Other issues that have been encountered in developing these animal vaccines include a relatively short duration of protective immunity, and a lack of effectiveness of inactivated vaccines. On the other hand, they have been relatively cheap to make and lend themselves to mass vaccination procedures.


Assuntos
Infecções por Coronavirus/veterinária , Gado , Animais de Estimação , Vacinação/veterinária , Vacinas Virais/uso terapêutico , Animais , Gatos , Bovinos , Infecções por Coronavirus/prevenção & controle , Cães , Aves Domésticas , Suínos
20.
Acta Virol ; 64(2): 216-225, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32551789

RESUMO

Currently, Slovakia is a rabies-free country, but the epizootiological situation of rabies was not always favorable. The main reservoir species of rabies virus in the first half of the last century was the domestic dog. Since 1906, hundreds of cases were reported, of which approximately 90% were infected dogs. The disease had a typical urban character. Since 1929, the number of rabid domestic animals decreased due to the implementation of dog vaccination campaigns in particular parts of Slovakia. From the second half of 1950s, red foxes (Vulpes vulpes) have become an important reservoir of the RABV. In this time period urban rabies in Slovakia changed into sylvatic form. One effective method of prevention and control of wildlife rabies is an oral rabies vaccination of red foxes. It is carried out in Slovakia since 1993. A detailed development of the rabies epizootiological situation on the territory of the Slovak Republic until the application of oral antirabies immunisation of foxes and the current situation after its performance is the main object of this review. Keywords: rabies; Lyssavirus; red fox; incidence; oral vaccination.


Assuntos
Vacinas Antirrábicas , Vírus da Raiva , Raiva , Animais , Animais Selvagens , Cães/virologia , Raposas/virologia , Raiva/epidemiologia , Raiva/prevenção & controle , Raiva/veterinária , Eslováquia/epidemiologia , Vacinação/veterinária
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