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1.
J Zoo Wildl Med ; 50(4): 778-789, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31926507

RESUMO

Data on canine distemper virus (CDV) vaccination were collected on 812 large felids (351 tigers, Panthera tigris; 220 lions, Panthera leo; 143 snow leopards, Panthera uncia; 50 leopards, Panthera pardus; and 48 jaguars, Panthera onca) from 48 institutions to assess vaccine use and safety. The documented individual vaccination events with multiple products numbered 2,846. Canarypox-vectored CDV vaccines were the most commonly used vaccines (96.3% of all vaccinations) and the Purevax® Ferret Distemper (PFD) vaccine was the most commonly used canarypox-vectored vaccine (91.0% of all vaccinations). Modified live virus (MLV) CDV vaccines were used for 3.7% of all vaccinations, and only in tigers, lions, and snow leopards. Adverse effects were reported after 0.5% (13 of 2,740) of the canarypox-vectored vaccinations and after 2.9% (3 of 104) of the MLV CDV vaccinations. This low complication rate suggests large felids may not be as sensitive to adverse effects of MLV CDV vaccines as other exotic carnivores. Serological data were available from 159 individuals (69 tigers, 31 lions, 31 snow leopards, 22 jaguars, and 6 Amur leopards, Panthera pardus orientalis) vaccinated with the PFD vaccine, and 66.0% of vaccinates seroconverted (defined as acquiring a titer ≥1: 24) at some point postvaccination: 24.3% after one vaccination, 55.8% after two vaccinations, 54.3% after three vaccinations, and 79.2% after four or more vaccinations. Among animals exhibiting seroconversion after the initial PFD vaccinations, 88.9% still had titers ≥12 mo and ≥24 mo after the last vaccination, and 87.5% had titers ≥1: 24 at ≥36 mo after the last vaccination. The study was unable to assess fully the safety of vaccination with either canarypox-vectored or MLV CDV vaccines during gestation because of the small number of animals vaccinated while pregnant (n = 6, all vaccinated with PFD).


Assuntos
Anticorpos Antivirais/sangue , Vírus da Cinomose Canina , Cinomose/prevenção & controle , Panthera/imunologia , Vacinas Virais/imunologia , Animais , Cinomose/epidemiologia , Feminino , Masculino , América do Norte/epidemiologia , Soroconversão , Vacinas Atenuadas
2.
J Zoo Wildl Med ; 50(4): 798-802, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31926509

RESUMO

Two methods for delivering a canarypox-vectored canine distemper vaccine to tigers (Panthera tigris) and domestic cats (Felis catus) were investigated. Eight tigers were divided randomly into two vaccination groups: subcutaneous injection or topical tonsillar application. Each tiger received 2 ml of canine distemper virus (CDV) vaccine (Merial Ferret Distemper Vaccine). Blood was collected from tigers on days 0, 21, 35 or 37, and 112 post-initial vaccination (PIV). Domestic cats were divided randomly into four treatment groups: saline injection (negative controls), low- and high-dose oral, and subcutaneous vaccinates. Blood was collected from domestic cats on days 0, 7, 21, and 28 and 165 or 208 PIV. Sera were tested for CDV antibodies by virus neutralization. All individuals were seronegative at the beginning of the study. One tiger vaccinated subcutaneously developed a titer of 32 by day 35, which reduced to 16 by day 112. Another tiger vaccinated by tonsillar application developed a titer of 8 on day 112. All other tigers remained seronegative. Cats that received saline injection or oral vaccination remained seronegative at each sampling time. Domestic cats vaccinated subcutaneously developed titers ranging from 4 to >128 by day 28, and those re-bled at day 166 had titers of 16 or 64. The disparity in response between domestic cats and tigers may be due to species differences or it may represent a dose-dependent effect. Subcutaneous vaccination with canarypox-vectored Purevax Ferret Distemper® is safe and elicits persistent antibody titers in domestic cats vaccinated parenterally.


Assuntos
Vírus da Varíola dos Canários , Doenças do Gato/prevenção & controle , Vírus da Cinomose Canina/imunologia , Cinomose/prevenção & controle , Tigres/imunologia , Vacinas Virais/imunologia , Administração Oral , Animais , Anticorpos Antivirais/sangue , Doenças do Gato/imunologia , Doenças do Gato/virologia , Gatos , Feminino , Masculino , Vacinas Sintéticas
3.
J Zoo Wildl Med ; 50(4): 972-975, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31926530

RESUMO

This study evaluated the safety of and humoral response to the Merial Recombitek® recombinant canine distemper virus (rCDV) vaccine in maned wolves (n = 9, age 2-9 yr). All maned wolves had prior history of annual vaccination with the Merial Purevax® ferret rCDV vaccine. Serum neutralization (SN) to CDV was measured prior to initial vaccination with the rCDV Recombitek vaccine followed by a booster vaccination at 4-6 wk. Final SN titers were obtained at 13 wk post initial vaccination. The maned wolves developed no observable adverse side effects through the study. Pre-Recombitek vaccination SN titers ranged from negative to 1: 8. Postvaccination CDV titers ranged from negative to 1: 8, and were therefore below the range of that considered protective in domestic dogs.


Assuntos
Anticorpos Antivirais/sangue , Canidae , Vírus da Cinomose Canina/imunologia , Cinomose/prevenção & controle , Vacinas Virais/imunologia , Animais , Feminino , Masculino , Vacinas Virais/efeitos adversos
4.
Arch Virol ; 165(1): 145-156, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31745717

RESUMO

Bovine viral diarrhea virus (BVDV) is a major pathogen worldwide, causing significant economic losses to the livestock sector. In Uruguay, BVDV seroprevalence at the farm level is >80%. In this work, 2546 serum, blood or tissue samples collected from animals suspected of being affected by BVD between 2015 and 2017 were analyzed by reverse transcription PCR and sequencing. Analysis of the BVDV genomic regions 5'UTR/Npro, Npro and E2 revealed that BVDV-1a, 1i and 2b circulate in the country, with BVDV-1a being the most prevalent subtype. Population dynamics studies revealed that BVDV-1a has been circulating in our herds since ~1990. This subtype began to spread and evolve, accumulating point mutations at a rate of 3.48 × 10-3 substitutions/site/year, acquiring specific genetic characteristics that gave rise to two local genetic lineages of BVDV-1a. These lineages are divergent from those circulating worldwide, as well as the vaccine strain currently used in Uruguay. The most notable differences between field and vaccine strains were found in the E2 glycoprotein, suggesting that the amino acid substitutions could result in failure of cross-protection/neutralization after vaccination. This is the first study that compares Uruguayan BVDV field and vaccine strains with other BVDV strains from throughout the world. The results obtained in this study will be very useful for developing a suitable immunization program for BVDV in Uruguay by identifying local field strains as candidates for vaccine development.


Assuntos
Vírus da Diarreia Viral Bovina/classificação , Mutação Puntual , Análise de Sequência de RNA/métodos , Substituição de Aminoácidos , Animais , Bovinos , Vírus da Diarreia Viral Bovina/genética , Vírus da Diarreia Viral Bovina/imunologia , Evolução Molecular , Filogenia , Estudos Soroepidemiológicos , Uruguai , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia
5.
Mayo Clin Proc ; 94(12): 2572-2586, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31806107

RESUMO

Zika virus outbreaks have been explosive and unpredictable and have led to significant adverse health effects-as well as considerable public anxiety. Significant scientific work has resulted in multiple candidate vaccines that are now undergoing further clinical development, with several vaccines now in phase 2 clinical trials. In this review, we survey current vaccine efforts, preclinical and clinical results, and ethical and other concerns that directly bear on vaccine development. It is clear that the world needs safe and effective vaccines to protect against Zika virus infection. Whether such vaccines can be developed through to licensure and public availability absent significant financial investment by countries, and other barriers discussed within this article, remains uncertain.


Assuntos
Surtos de Doenças/prevenção & controle , Desenvolvimento de Medicamentos , Vacinas Virais , Infecção por Zika virus/prevenção & controle , Humanos , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/epidemiologia
6.
Mol Immunol ; 116: 180-190, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31704501

RESUMO

Infectious pancreatic necrosis virus (IPNV) and infectious hematopoietic necrosis virus (IHNV) are two common viral pathogens that cause severe economic losses in all salmonid species in culture, but especially in rainbow trout. Although vaccines against both diseases have been commercialized in some countries, no such vaccines are available for them in China. In this study, a recombinant virus was constructed using the IHNV U genogroup Blk94 virus as a backbone vector to express the antigenic gene, VP2, from IPNV via the reverse genetics system. The resulting recombinant virus (rBlk94-VP2) showed stable biological characteristics as confirmed by virus growth kinetic analyses, pathogenicity analyses, indirect immunofluorescence assays and western blotting. Rainbow trout were immunized with rBlk94-VP2 and then challenged with the IPNV ChRtm213 strain and the IHNV Sn1203 strain on day 45 post-vaccination. A significantly higher survival rate against IHNV was obtained in the rBlk94-VP2 group on day 45 post-vaccination (86%) compared with the PBS mock immunized group (2%). Additionally, IPNV loads decreased significantly in the rBlk94-VP2 immunized group in the liver (28.6-fold to 36.5-fold), anterior kidney (21.7-fold to 44.2-fold), and spleen (14.9-fold to 22.7-fold), as compared with the PBS mock control group. The mRNA transcripts for several innate and adaptive immune-related proteins (IFN-γ, IFN-1, Mx-1, CD4, CD8, IgM, and IgT) were also significantly upregulated after rBlk94-VP2 vaccination, and neutralizing antibodies against both IHNV and IPNV were induced on day 45 post-vaccination. Collectively, our results suggest that this recombinant virus could be developed as a vaccine vector to protect rainbow trout against two or more diseases, and our approach lays the foundations for developing live vaccines for rainbow trout.


Assuntos
Doenças dos Peixes/imunologia , Vírus da Necrose Hematopoética Infecciosa/imunologia , Oncorhynchus mykiss/imunologia , Oncorhynchus mykiss/virologia , Animais , Anticorpos Antivirais/imunologia , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/virologia , China , Rim Cefálico/imunologia , Rim Cefálico/virologia , Vírus da Necrose Pancreática Infecciosa/imunologia , Pancreatite Necrosante Aguda/imunologia , Pancreatite Necrosante Aguda/virologia , Infecções por Rhabdoviridae/imunologia , Infecções por Rhabdoviridae/virologia , Baço/imunologia , Baço/virologia , Vacinação/métodos , Vacinas de DNA/imunologia , Carga Viral/métodos , Vacinas Virais/imunologia
7.
Vet Microbiol ; 238: 108429, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31648721

RESUMO

Viral haemorrhagic disease (VHD) and colibacillosis are common diseases in rabbits that cause economic losses worldwide. The effect of colibacillosis on the immune response of vaccinated rabbits against rabbit haemorrhagic disease virus (RHDV) was studied. Four groups (G1-G4) were included. G1 was the negative control group; G2 was the RHDV vaccine group; G3 was the E. coli-infected group; and G4 was the E. coli-infected + RHDV vaccine group. The E. coli infection and RHDV vaccination were simultaneously performed, with another previous infection, 3 days before vaccination. At 28 days post-vaccination (PV), the rabbits (G2-G4) were challenged intramuscularly with 0.5 ml of RHDV at a dose of 103 50% median lethal dose (LD50)/rabbit. The rabbits were observed for clinical signs, body weight gain and mortality rates. Tissue, blood, serum, and faecal samples and rectal swabs were collected at 3, 5, 7, 14, 21 and 28 days PV. Significant clinical signs and mortality and a decrease in BW were observed in the infected + RHDV vaccine group. On the 3rd day post-infection (PI), compared with all the other groups, the vaccinated group (G2) had significantly upregulated hepatic tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels; however, the infected + RHDV vaccine group had significantly higher intestinal levels of TNF-α and IL-6 than the other groups. Furthermore, E. coli infection in vaccinated rabbits led to immunosuppression, as shown by significant decreases (P < 0.05) in heterophil phagocytic activity, the CD4+/CD8+ ratio, and HI antibody responses to RHDV and a significant increase in the heterophil to lymphocyte (H/L) ratio. In conclusion, colibacillosis leads to immunosuppression involving a shift in the equilibrium of cytokines and reduced weight gain and mortality in vaccinated rabbits and could be a contributing factor in RHDV vaccination failure in rabbit farming.


Assuntos
Infecções por Caliciviridae/veterinária , Infecções por Escherichia coli/veterinária , Coelhos/imunologia , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Infecções por Caliciviridae/imunologia , Infecções por Caliciviridae/mortalidade , Citocinas/genética , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/mortalidade , Infecções por Escherichia coli/fisiopatologia , Regulação da Expressão Gênica/imunologia , Vírus da Doença Hemorrágica de Coelhos/imunologia , Coelhos/microbiologia , Coelhos/virologia , Vacinação/normas
8.
Rev Med Suisse ; 15(666): 1825-1830, 2019 Oct 09.
Artigo em Francês | MEDLINE | ID: mdl-31599524

RESUMO

Viral infections are extremely common and generally self-restricted, thus antiviral therapy is limited to precise indications. Apart from HIV (not reviewed in this article), the principal treatable viruses are HSV 1 and 2, VZV, CMV, Influenza A and B, and hepatitis B and C. Vaccination is another cornerstone of viral infections control. This article summarizes actual and available therapy. New treatments arrived recently on the market or are being developed : HCV can now be treated with a high success rate, baloxavir against the flu, a new zoster vaccine will probably soon be available in Switzerland and letermovir improves CMV prophylaxis in the case of hematopoietic stem cell transplant.


Assuntos
Antivirais/uso terapêutico , Medicina Geral , Viroses/tratamento farmacológico , Clínicos Gerais , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Suíça , Vacinas Virais/provisão & distribução , Viroses/prevenção & controle , Viroses/virologia
9.
Vet Ital ; 55(3): 231-239, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31599547

RESUMO

Egypt has a large traditional and exotic poultry sector which is challenged regularly by poultry diseases in endemic and epidemic proportions. The household poultry in particular is a source of livelihoods and employment for millions of low income citizens. Highly pathogenic avian influenza (HPAI) H5N1 and Newcastle disease are the most important poultry diseases in this sector. Whereas poultry vaccines are available to reduce the incidence of disease in Egypt, their effectiveness is doubtful. We conducted a biological evaluation of selected viral vaccines of poultry in three governorates in Egypt. Fifty­four percent of the vaccines had reduced vaccine titres and the effect of secondary vaccine distributions was associated with the observed vaccine titres. External contamination was observed in some vaccines and break in cold chain was reported. Whereas no vaccine distributor used purpose­built vaccine refrigerator, none also had prescribed protocol for vaccine handling or kept record of vaccine. There is a need to review vaccine handling procedure, monitor of vaccine cold chain more critically and review the whole chain that support vaccine distributions in Egypt.


Assuntos
Galinhas , Doenças das Aves Domésticas/prevenção & controle , Vacinação/veterinária , Vacinas Virais/uso terapêutico , Animais , Egito , Doenças das Aves Domésticas/virologia , Vacinação/métodos
10.
Nat Commun ; 10(1): 4606, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601808

RESUMO

The current leading Zika vaccine candidates in clinical testing are based on live or killed virus platforms, which have safety issues, especially in pregnant women. Zika subunit vaccines, however, have shown poor performance in preclinical studies, most likely because the antigens tested do not display critical quaternary structure epitopes present on Zika E protein homodimers that cover the surface of the virus. Here, we produce stable recombinant E protein homodimers that are recognized by strongly neutralizing Zika specific monoclonal antibodies. In mice, the dimeric antigen stimulate strongly neutralizing antibodies that target epitopes that are similar to epitopes recognized by human antibodies following natural Zika virus infection. The monomer antigen stimulates low levels of E-domain III targeting neutralizing antibodies. In a Zika challenge model, only E dimer antigen stimulates protective antibodies, not the monomer. These results highlight the importance of mimicking the highly structured flavivirus surface when designing subunit vaccines.


Assuntos
Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/metabolismo , Vacinas Virais/imunologia , Zika virus/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Epitopos/imunologia , Feminino , Humanos , Camundongos Endogâmicos C57BL , Multimerização Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Células Vero , Proteínas do Envelope Viral/genética , Zika virus/genética , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologia
11.
BMC Vet Res ; 15(1): 342, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619295

RESUMO

BACKGROUND: The objective of this study was to assess the efficacy of a trivalent vaccine mixture and compare it to the respective monovalent vaccines against Mycoplasma hyopneumoniae, porcine circovirus type 2 (PCV2), and porcine reproductive and respiratory syndrome virus (PRRSV). RESULTS: Pigs that were triple challenged with M. hyopneumoniae, PCV2, and PRRSV following vaccination with the trivalent vaccine mixture exhibited a significantly better growth performance when compared to unvaccinated and challenged pigs. A statistical difference was not found when comparing pig populations which were vaccinated with the trivalent vaccine followed by a triple challenge and pigs vaccinated with monovalent M hyopneumoniae vaccine followed by mycoplasmal single challenge in the following areas: M. hyopneumoniae nasal shedding, the number of M. hyopneumoniae-specific interferon-γ secreting cells (IFN-γ-SC), and mycoplasmal lung lesion scores. Pigs vaccinated with the trivalent vaccine mixture followed by a triple challenge resulted in a similar reduction of PCV2 viremia, an increase in the number of PCV2-specific IFN-γ-SC and reduction in interstitial lung lesion scores when compared to pigs vaccinated with a PCV-2 vaccine and challenged with PCV2 only. Lastly, there was a significant difference in the reduction of PRRSV viremia, an increase in PRRSV-specific IFN-γ-SC and a reduction of interstitial lung lesion scores between pigs vaccinated with the trivalent vaccine mixture followed by a triple challenge and pigs vaccinated with a monovalent PRRSV vaccine followed by PRRSV challenge only. CONCLUSION: The trivalent vaccine mixture was efficacious against a triple challenge of M. hyopneumoniae, PCV2, and PRRSV. The trivalent vaccine mixture, however, did not result in equal protection when compared against each respective monovalent vaccine, with the largest vaccine occurring within PRRSV.


Assuntos
Circovirus/imunologia , Mycoplasma hyopneumoniae/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Doenças dos Suínos/prevenção & controle , Vacinação/veterinária , Animais , Vacinas Bacterianas/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Feminino , Masculino , Pneumonia Suína Micoplasmática/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Sus scrofa , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia , Doenças dos Suínos/virologia , Vacinas Combinadas/administração & dosagem , Vacinas Combinadas/imunologia , Vacinas Virais/imunologia
12.
PLoS Genet ; 15(10): e1008271, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31622336

RESUMO

Viral quasispecies refers to a population structure that consists of extremely large numbers of variant genomes, termed mutant spectra, mutant swarms or mutant clouds. Fueled by high mutation rates, mutants arise continually, and they change in relative frequency as viral replication proceeds. The term quasispecies was adopted from a theory of the origin of life in which primitive replicons) consisted of mutant distributions, as found experimentally with present day RNA viruses. The theory provided a new definition of wild type, and a conceptual framework for the interpretation of the adaptive potential of RNA viruses that contrasted with classical studies based on consensus sequences. Standard clonal analyses and deep sequencing methodologies have confirmed the presence of myriads of mutant genomes in viral populations, and their participation in adaptive processes. The quasispecies concept applies to any biological entity, but its impact is more evident when the genome size is limited and the mutation rate is high. This is the case of the RNA viruses, ubiquitous in our biosphere, and that comprise many important pathogens. In virology, quasispecies are defined as complex distributions of closely related variant genomes subjected to genetic variation, competition and selection, and that may act as a unit of selection. Despite being an integral part of their replication, high mutation rates have an upper limit compatible with inheritable information. Crossing such a limit leads to RNA virus extinction, a transition that is the basis of an antiviral design termed lethal mutagenesis.


Assuntos
Quase-Espécies , Vírus de RNA/fisiologia , Evolução Molecular , Sequenciamento de Nucleotídeos em Larga Escala , Taxa de Mutação , Origem da Vida , Vírus de RNA/genética , Vírus de RNA/imunologia , Vacinas Virais/imunologia , Replicação Viral
13.
Vet Microbiol ; 237: 108403, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31585656

RESUMO

Classical swine fever (CSF) still threatens the swine industry in China, with genotype 2 isolates of CSFV dominating the epizootics. In 2018 the first E2 subunit marker vaccine against CSFV (Tian Wen Jing, TWJ-E2®), containing a baculovirus-expressed E2 glycoprotein of a genotype 1.1 vaccine strain, was officially licensed in China and commercialized. To evaluate the cross-protective efficacy of TWJ-E2 against different virulent genotype 2 Chinese field isolates (2.1b, 2.1c, 2.1 h, and 2.2), 4-week-old pigs were immunized with the TWJ-E2 vaccine according to the manufacturer's instructions and then challenged with genotype 2 strains. A group vaccinated with the conventional C-strain vaccine was included for comparison. TWJ-E2 vaccinated pigs developed higher levels of E2 and neutralizing antibodies than those receiving the commercial C-strain vaccine. All TWJ-E2 and C-strain vaccinated pigs survived challenge without development of fever, clinical signs or pathological lesions. In contrast, all unvaccinated control pigs displayed severe CSF disease with 40-100% mortalities by 24 days post challenge. None of the TWJ-E2 and C-strain vaccinated pigs developed viremia, viral shedding from tonsils, Erns protein in the sera, or viral RNA loads in different tissues after challenge, all of which were detected in the challenged unvaccinated controls. We conclude that vaccination of young pigs with TWJ-E2 provides complete immune protection against genotypically heterologous CSFVs and prevents viral shedding after challenge, with an efficacy at least comparable to that elicited by the conventional C-strain vaccine.


Assuntos
Vírus da Febre Suína Clássica/genética , Peste Suína Clássica/prevenção & controle , Genótipo , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/genética , Anticorpos Antivirais/sangue , Subunidades Proteicas/imunologia , Suínos , Vacinas de Subunidades
14.
Vet Clin North Am Food Anim Pract ; 35(3): 575-592, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31590903

RESUMO

Vaccination is a critical component of cattle health management. Effective cattle vaccine programs should consider the timing of vaccination in relation to expected disease challenge, risk for wild-type exposure of various bovine pathogens, and host factors during vaccination. Nearly all consulting veterinarians recommend vaccination of stressed, high-risk calves on feedlot arrival. However, this recommendation fails to consider several factors associated with vaccine efficiency. Further research evaluating vaccine interactions in stressed cattle and potential additive effects of endotoxin from multiple bacterin administration may reveal new evidence-based vaccination guidelines for cattle in the various segments of beef and dairy production systems.


Assuntos
Bovinos/imunologia , Carne Vermelha , Vacinação/veterinária , Animais , Doenças dos Bovinos/prevenção & controle , Vacinação/métodos , Vacinas Virais/administração & dosagem
15.
Arch Virol ; 164(12): 2975-2984, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31570994

RESUMO

Coxsackievirus A16 (CV-A16) is one of the main causative agents of hand, foot and mouth disease (HFMD) in young children and has become prevalent in the Asia-Pacific region in recent years. However, no approved vaccines or drugs are available for CV-A16 infection. CV-A16 virus-like particles (VLPs) are a potential vaccine candidate; however, whether the intranasal route of immunization is suitable for inducing immune responses against CV-A16 infection has not been clarified. In this study, the comprehensive immunogenicity and protective efficacy of the CV-A16 VLP vaccine were evaluated by multiple methods in a mouse model. In mice, a high neutralizing antibody (NTAb) titre could be elicited by intranasal immunization with CV-A16 VLPs, which produced NTAb levels similar to those induced by intranasal immunization with inactivated CV-A16. Passive immunity with NTAbs provided very good protection, as the survival rate of the immunized neonatal mice was 100% after challenges with CV-A16 at a dose of 1000 LD50. Passive protective effects were transferred to the neonates via the mother, thus protecting all the pups against challenges with the homologous or heterologous strains of CV-A16 at a dose of 1000 LD50. In addition, intranasal immunization with CV-A16 VLPs also induced the production of mucosal secretory IgA (s-IgA) antibodies, which may inhibit CV-A16 virus invasion. This study provides valuable supplemental information to facilitate our understanding of the specific protective efficacy of CV-A16 VLPs and has significance for development of the candidate vaccine into a safe and effective vaccine.


Assuntos
Enterovirus Humano A/imunologia , Infecções por Enterovirus/prevenção & controle , Nariz/virologia , Vacinas Virais/administração & dosagem , Animais , Animais Recém-Nascidos , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Modelos Animais de Doenças , Enterovirus Humano A/genética , Infecções por Enterovirus/imunologia , Infecções por Enterovirus/virologia , Feminino , Humanos , Imunização , Camundongos , Camundongos Endogâmicos ICR , Vacinas Virais/genética , Vacinas Virais/imunologia
16.
Can J Vet Res ; 83(4): 248-254, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31571723

RESUMO

The objective of the present study was to evaluate the efficacy of a commercial porcine reproductive and respiratory syndrome virus (PRRSV) subunit vaccine against heterologous PRRSV-1 and PRRSV-2 challenge in late-term pregnant gilts. Gilts were vaccinated intramuscularly 56 and 35 days antepartum (on days 58 and 79 of gestation) and challenged intranasally 21 days antepartum (on day 93 of gestation) with PRRSV-1 or PRRSV-2. Regardless of the challenge strain's genotype, the vaccinated gilts carried their pregnancies to term and farrowed between days 114 and 115 of gestation. All the unvaccinated gilts aborted, between days 105 and 110 of gestation. The vaccinated gilts had a significantly lower level (P < 0.05) of PRRSV viremia and significantly higher levels (P < 0.05) of virus-neutralizing antibodies and interferon-γ-secreting cells compared with the unvaccinated gilts. The mean number of PRRSV-positive cells per area of fetal tissue examined did not differ significantly between the litters from the vaccinated and unvaccinated gilts. The data presented here indicate that vaccination in late-term pregnancy with PRRSV subunit vaccine is efficacious against reproductive failure due to heterologous PRRSV-1 and PRRSV-2 infection.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Complicações Infecciosas na Gravidez/veterinária , Vacinas Virais/imunologia , Animais , Feminino , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Subunidades Proteicas , Suínos , Vacinas de Subunidades/imunologia , Proteínas Virais/imunologia
17.
Can J Vet Res ; 83(4): 313-316, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31571732

RESUMO

The objective of this study was to evaluate the effect of late-gestation vaccination of beef heifers with 2 doses of a killed-virus (KV) vaccine containing bovine herpesvirus 1 (BoHV-1), bovine viral diarrhea virus 1 (BVDV-1), and bovine viral diarrhea virus 2 (BVDV-2) on the serum concentrations of antibody against BoHV-1, BVDV-1, and BVDV-2 in heifers and their calves and on the IgG concentration in the calves. Of the 47 pregnant beef heifers selected, 26 received 2 doses of the vaccine at 6.5 to 8 mo of gestation (at pregnancy check), and 21 received 2 doses of saline. The mean log2 serum titers of neutralizing antibody against BoHV-1, BVDV-1, and BVDV-2 before vaccination did not differ significantly between the treatment groups; however, at calving all 3 mean titers were significantly greater (P < 0.05) in the vaccinated heifers than in the control heifers. At 24 h after birth the mean serum IgG levels in the calves did not differ significantly between the 2 groups, at 30.18 and 32.28 g/L, respectively (P < 0.05); however, the mean log2 serum titers of antibody to all 3 viruses were greater in the calves nursing colostrum from the vaccinated heifers than in the calves nursing colostrum from the nonvaccinated heifers and significantly so for BoHV-1 and BVDV-1 (P < 0.001 and P = 0.009, respectively). Thus, late-gestation vaccination of beef heifers could result in a greater and more consistent deposition of specific antibodies in colostrum, reducing the variability of initial titers in calves and increasing the duration of maternal immunity.


Assuntos
Anticorpos Antivirais/sangue , Doenças dos Bovinos/prevenção & controle , Vírus da Diarreia Viral Bovina/imunologia , Herpesvirus Bovino 1/imunologia , Imunoglobulina G/sangue , Vacinas Virais/imunologia , Animais , Especificidade de Anticorpos , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/imunologia , Feminino , Imunidade Materno-Adquirida , Gravidez , Vacinação/veterinária
18.
Int J Nanomedicine ; 14: 7533-7548, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571862

RESUMO

Background: The influenza A virus (IAV) is known for its high variability and poses a huge threat to the health of humans and animals. Pigs play a central role in the cross-species reassortment of IAV. Ectodomain of matrix protein 2 (M2e) is the most conserved protective antigen in IAV and can be used to develop nanovaccines through nanoparticles displaying to increase its immunogenicity. However, the high immunogenicity of nanoparticles can cause the risk of off-target immune response, and excess unwanted antibodies may interfere with the protective efficacy of M2e-specific antibodies. Therefore, it is necessary to select reasonable nanoparticles to make full use of antibodies against nanoparticles while increasing the level of M2e-specific antibodies. Porcine circovirus type 2 (PCV2) is the most susceptible virus in pigs and can promote IAV infection. It is meaningful to develop a vaccine that can simultaneously control swine influenza virus (SIV) and PCV2. Methods: In the present study, M2e of different copy numbers were inserted into the capsid (Cap) protein of PCV2 and expressed in Escherichia coli to form self-assembled chimeric virus-like particles (VLPs) nanovaccine. BALB/c mice and pigs were immunized with these nanovaccines to explore optimal anti-IAV and anti-PCV2 immunity. Results: Cap is capable of carrying at least 81 amino acid residues (three copies of M2e) at its C-terminal without impairing VLPs formation. Cap-3M2e VLPs induced the highest levels of M2e-specific immune responses, conferring protection against lethal challenge of IAVs from different species and induced specific immune responses consistent with PCV2 commercial vaccines in mice. In addition, Cap-3M2e VLPs induced high levels of M2e-specific antibodies and PCV2-specific neutralizing antibodies in pigs. Conclusion: Cap-3M2e VLP is an economical and promising bivalent nanovaccine, which provides dual protection against IAV and PCV2.


Assuntos
Circovirus/imunologia , Vírus da Influenza A/imunologia , Nanopartículas/uso terapêutico , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Especificidade de Anticorpos/imunologia , Aves/virologia , Proteínas do Capsídeo/química , Proliferação de Células , Citocinas/metabolismo , Cães , Feminino , Humanos , Imunidade Humoral , Influenza Aviária/imunologia , Influenza Aviária/prevenção & controle , Influenza Aviária/virologia , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Linfócitos/citologia , Células Madin Darby de Rim Canino , Camundongos Endogâmicos BALB C , Testes de Neutralização , Proteínas Recombinantes/isolamento & purificação , Suínos , Vírion/imunologia , Vírion/ultraestrutura
19.
PLoS Pathog ; 15(9): e1008043, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31568492

RESUMO

Immunization vectors based on cytomegalovirus (CMV) have attracted a lot of interest in recent years because of their high efficacy in the simian immunodeficiency virus (SIV) macaque model, which has been attributed to their ability to induce strong, unusually broad, and unconventionally restricted CD8+ T cell responses. To evaluate the ability of CMV-based vectors to mediate protection by other immune mechanisms, we evaluated a mouse CMV (MCMV)-based vector encoding Friend virus (FV) envelope (Env), which lacks any known CD8+ T cell epitopes, for its protective efficacy in the FV mouse model. When we immunized highly FV-susceptible mice with the Env-encoding MCMV vector (MCMV.env), we could detect high frequencies of Env-specific CD4+ T cells after a single immunization. While the control of an early FV challenge infection was highly variable, an FV infection applied later after immunization was tightly controlled by almost all immunized mice. Protection of mice correlated with their ability to mount a robust anamnestic neutralizing antibody response upon FV infection, but Env-specific CD4+ T cells also produced appreciable levels of interferon γ. Depletion and transfer experiments underlined the important role of antibodies for control of FV infection but also showed that while no Env-specific CD8+ T cells were induced by the MCMV.env vaccine, the presence of CD8+ T cells at the time of FV challenge was required. The immunity induced by MCMV.env immunization was long-lasting, but was restricted to MCMV naïve animals. Taken together, our results demonstrate a novel mode of action of a CMV-based vaccine for anti-retrovirus immunization that confers strong protection from retrovirus challenge, which is conferred by CD4+ T cells and antibodies.


Assuntos
Vírus da Leucemia Murina de Friend/imunologia , Muromegalovirus/imunologia , Vacinas Virais/imunologia , Transferência Adotiva , Animais , Anticorpos Antivirais/biossíntese , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Feminino , Vírus da Leucemia Murina de Friend/genética , Vírus da Leucemia Murina de Friend/patogenicidade , Produtos do Gene env/genética , Produtos do Gene env/imunologia , Vetores Genéticos , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Muromegalovirus/genética , Infecções por Retroviridae/imunologia , Infecções por Retroviridae/prevenção & controle , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/genética
20.
Med. clín (Ed. impr.) ; 153(7): 276-280, oct. 2019. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-185336

RESUMO

Introducción y objetivo: La parotiditis se caracteriza por la inflamación de la glándula parótida y fiebre, y es prevenible mediante vacunación con triple vírica (TV). El objetivo es evaluar el impacto y la efectividad vacunal (EV). Material y métodos: Se seleccionaron los casos notificados al Sistema de Enfermedades de Declaración Obligatoria entre 1998 y 2016. La EV se calculó en cohortes vacunadas con 2 dosis de Jeryl-Lynn, y el impacto comparando las incidencias por edad y por cohortes Rubini (1995-1998) y Jeryl-Lynn (1999-2002) en los periodos 1998-2004, 2005-2009 y 2010-2015. Las estimaciones por grupo de edad y período se compararon con las del período anterior y las estimaciones por cohortes se compararon entre sí dentro de cada período mediante razones de incidencia (RI) empleando modelos de Poisson. La EV se estimó empleando el método de cribado mediante modelos de regresión logística. Resultados: Se notificaron 13.816 casos. La incidencia en 2005-2009 fue superior a la de 1998-2004 (RI: 1,46; IC 95%: 1,40-1,53), y en 2010-2015 se mantuvo estable (RI: 0,99; IC 95%: 0,95-1,03). La incidencia anual media de las cohortes Rubini fue de 69,43 casos por 100.000 habitantes y la de las cohortes Jeryl-Lynn de 32,24. La RI fue de 0,25 (IC 95%: 0,22-0,29), 0,55 (IC 95%: 0,49-0,61) y 0,88 (IC 95%: 0,76-1,00) para cada periodo, respectivamente. Se incluyeron 2.574 casos en el estudio de EV. La EV disminuyó con el tiempo al alcanzar valores no significativos tras 7 años de seguimiento (EV: 55%; IC 95%: 82 a -12%). Conclusiones: El comportamiento de la parotiditis se caracteriza por presentar fluctuaciones, cambios en la presentación etaria y una disminución de la EV


Introduction: Mumps is characterised by parotid inflammation and fever and is preventable by vaccination with MMR vaccine. The objective of the study is to assess the impact and effectiveness of the vaccine. Material and methods: Cases notified to the Notifiable Disease System between 1998 and 2016 were used for the study. The vaccine effectiveness (VE) was calculated in cohorts vaccinated with two doses of Jeryl-Lynn, and the impact was calculated by comparing incidences by age and by Rubini (1995-1998) and Jeryl-Lynn (1999-2002) cohorts during the periods 1998-2004, 2005-2009 and 2010-2015. The incidences for age group and period were compared with the previous period and the incidences for cohorts were compared within a period with incidence ratios (IR) using Poisson models. The VE was estimated using the screening method using logistic regression models. Results: 13,816 cases were reported. The incidence in 2005-2009 was higher than in 1998-2004 (IR: 1.46, 95% CI: 1.40-1.53), and it remained stable in 2010-2015 (IR: 0.99, 95% CI: 0.95-1.03). The average incidence rate of the Rubini cohort was 69.43 and the Jeryl-Lynn cohort was 32.24. The IR was 0.25 (95% CI: 0.22-0.29), 0.55 (95% CI: 0.49-0.61) and 0.88 (95% CI: 0.76-1.00) for each period respectively. 2,574 cases were included in the VE study. EV decreased over time reaching not significant values after seven years of follow-up (VE: 55%, 95% CI: 82 to -12%). Conclusions: Parotiditis behavior is characterised by fluctuations, changes in presentation and a decrease in VE


Assuntos
Humanos , Parotidite/epidemiologia , Vacina contra Difteria, Tétano e Coqueluche , Vacina contra Sarampo-Caxumba-Rubéola/administração & dosagem , Vacinas Virais , Resultado do Tratamento , Caxumba/imunologia , Parotidite/imunologia , Testes de Neutralização , Modelos Logísticos , Vírus da Caxumba/imunologia , Vacina contra Caxumba , Intervalos de Confiança , Monitoramento Epidemiológico
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