RESUMO
The meeting was opened with a presentation analyzing COHEFA 12’s request in Resolution 4, which asked COSALFA to examine the requirements and conditions of biological biosafety necessary to review the restrictions imposed to the handling of FMD virus strains exogenous to the region. These restrictions derive from Resolution IX of COSALFA 28 meeting, which established the inconvenience of introducing/maintaining/handling foot-and-mouth virus strains exogenous to the region due to the potential of viral escape with the resulting consequences for the health of herds and the agricultural economy of the Region.
Assuntos
Febre Aftosa , Aphthovirus , Saúde Pública Veterinária , Vírus da Febre AftosaRESUMO
Abstract The foot and mouth disease virus (FMDV) is sensitive to acids and can be inactivated by exposure to low pH conditions. Spraying animals at risk of infection with suspensions of acid-forming microorganisms has been identified as a potential strategy for preventing FMD. Kombucha is one of the most strongly acid-forming symbiotic probiotics and could thus be an effective agent with which to implement this strategy. Moreover, certain Chinese herbal extracts are known to have broad-spectrum antiviral effects. Chinese herbal kombucha can be prepared by fermenting Chinese herbal extracts with a kombucha culture. Previous studies demonstrated that Chinese herbal kombucha prepared in this way efficiently inhibits FMDV replication in vitro. To assess the inhibitory effects of Chinese herbal kombucha against FMDV in vitro, swine challenged by intramuscular injection with 1000 SID50 of swine FMDV serotype O strain O/China/99 after treatment with Chinese herbal kombucha were partially protected against infection, as demonstrated by a lack of clinical symptoms and qRT-PCR analysis. In a large scale field trial, spraying cattle in an FMD outbreak zone with kombucha protected against infection. Chinese herbal kombucha may be a useful probiotic agent for managing FMD outbreaks.(AU)
Assuntos
Medicamentos de Ervas Chinesas/administração & dosagem , AphthovirusRESUMO
There is a distinct age-associated susceptibility of horses to Rhodococcus equi infection. Initial infection is thought to occur in the neonatal and perinatal period, and only foals less than 6 months of age are typically affected. R. equi is closely related and structurally similar to Mycobacterium tuberculosis, and causes similar pathologic lesions. Protective immune responses to M. tuberculosis involve classical major histocompatibility complex (MHC)-restricted T cells that recognize peptide antigen, as well as MHC-independent T cells that recognize mycobacterial lipid antigen presented by CD1 molecules. Given the structural similarity between these two pathogens and our previous observations regarding R. equi-specific, MHC-unrestricted cytotoxic T lymphocytes (CTL), we developed 3 related hypotheses: (1) CD1 molecules are expressed on equine antigen presenting cells (APC), (2) CD1 expression on APC is less in foals compared to adults and (3) infection with live virulent R. equi induces up-regulation of CD1 on both adult and perinatal APC. CD1 expression was examined by flow cytometric analysis using a panel of monoclonal CD1 antibodies with different species and isoform specificities. RESULTS: Three CD1 antibodies specific for CD1b showed consistent cross reactivity with both foal and adult monocyte-derived macrophages (MDM). CD1b and MHC class II expression were significantly higher on adult MDM compared with foals. R. equi infected MDM showed significantly lower expression of CD1b, suggesting that infection with this bacterium induces down-regulation of CD1b on the cell surface. Histograms from dual antibody staining of peripheral blood mononuclear cells also revealed that 45-71% of the monocyte population stained positive for CD1b, and that the majority of these also co-expressed MHC II molecules, indicating that they were APC. The anti-CD1 antibodies showed no binding or minimal binding to bronchoalveolar lavage (BAL)-derived macrophages.
Assuntos
Animais , Antígenos CD1 , Aphthovirus , Rhodococcus equi , Adenovírus HumanosRESUMO
The use of foot-and-mouth disease (FMD) vaccines that do not induce antibodies against non-structural proteins (NSP) is extremely relevant for the demonstration of regions "free of FMDV infection" and control strategies. In this study cattle were primed and boosted with five doses of oil vaccines containing high antigenic payloads on days 0, 90, 130, 160 and 200. The serological response against NSP was measured using four commercially available assays: two 3ABC-ELISAs; one 3B-ELISA (and complementary 3A-ELISA) and an enzyme-immunotransfer blot assay (EITB). Additionally, locally produced NSP antibodies detection reagents and VIAA antibodies were evaluated. A high level of specific immune response against vaccine strains was shown. After four doses of vaccine, non-reactive animals were detected by any of the NSP assays. After the fifth immunization, 2 of 17 animals were reactive in one ELISA kit, but these samples proved negative by confirmatory tests. Antibodies against NSP were not detected in single dose immunized cattle. The principle of the NSP-ELISA used as a screening test for large sero-surveys in South America is established and this paper emphasizes the importance of using vaccines that have demonstrated no interference with NSP antibodies detection assays.
Assuntos
Anticorpos Antivirais/sangue , Aphthovirus/imunologia , Doenças dos Bovinos/imunologia , Proteínas não Estruturais Virais/imunologia , Vacinas Virais/imunologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/virologia , Ensaio de Imunoadsorção Enzimática/veterinária , Febre Aftosa/prevenção & controleRESUMO
In the present report, we characterized the immune response and the protection conferred by recombinant baculoviruses or infected insect cells expressing the fusions gp64-P1 and gp64-site A FMDV antigens. Mice, vaccinated intraperitoneally with gp64-P1 immunogens, showed a low-antibody response and a variable degree of protection. However, when mice received recombinant baculoviruses or infected insect cells expressing the fusion protein gp64-site A, high-ELISA and seroneutralizing titers (SNT) against FMDV were elicited. All mice immunized with Sf9 cells expressing FMDV site A developed a protective immune response against challenge with virulent FMDV, indicating that the baculovirus display of foreign epitopes is a promising approach to biosynthetic vaccines.
Assuntos
Aphthovirus/imunologia , Cisteína Endopeptidases/imunologia , Proteínas Virais de Fusão/imunologia , Proteínas Virais/imunologia , Proteases Virais 3C , Animais , Aphthovirus/genética , Baculoviridae/genética , Células Cultivadas , Cisteína Endopeptidases/genética , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Spodoptera/citologia , Proteínas Virais de Fusão/genética , Proteínas Virais/genéticaRESUMO
[Histórico] La fiebre aftosa fue introducida al Continente Americano, a través de la importación de animales de Europa, por la necesidad de mejorar la productividad de la ganadería bovina, para atender a la creciente industria de procesamiento de productos de origen animal del Cono Sur del Subcontinente. La primera introducción registrada fue en la Provincia de Buenos Aires, Argentina, alrededor de 1870. Desde entonces, la enfermedad se ha difundido a los países vecinos por las relaciones comerciales existentes entre ellos y con otros en el Continente Americano. Esta situación caracterizó a Sudamérica como endémica y provocó el embargo de países de Europa y de los Estados Unidos, a productos de origen animal, en especial de Argentina, Brasil y Uruguay, tradicionales exportadores.
Assuntos
Febre Aftosa , Aphthovirus , Medição de Risco , América do SulRESUMO
[Introducción] Desde hace varias décadas que algunos de los países sudamericanos vienen produciendo y controlando la calidad (inocuidad, esterilidad y potencia) de vacunas antiaftosa. Destácase en este período el marco que ha representado la reunión realizada en Octubre de 1985, en el Centro Panamericano de Fiebre Aftosa (PANAFTOSA/OPS/OMS), del Research Group of Standig Technical Commitee of the European Commission for the Control of Footand-Mouth Disease (STC-ECFMD). En esta reunión se ha analizado entre otros puntos, el tema relativo a la evaluación y control de la potencia de las vacunas antiaftosa y la importancia de este control desde el punto de vista del usuario del biológico, del productor y del controlador oficial. Se han presentado resultados de la experiencia europea y sudamericana.
Assuntos
Febre Aftosa , Aphthovirus , Vacinas , Potência , Controle de QualidadeRESUMO
Los progresos realizados en tecnología de productos biológicos y la demanda por parte del consumidor de aumentar la relación calidad/ precio, han impulsado no solamente un perfeccionamiento en las técnicas de control de calidad del producto final sino la implementación de sistemas de control de calidad del proceso de producción de los biológicos. En consecuencia el producto es totalmente monitoreado desde la materia prima utilizada en su producción hasta el producto final para consumo. Al ser empleado sistema de garantía de calidad durante el proceso de manufactura, el riesgo de obtener resultados negativos en el control del producto final se ha visto reducido o prácticamente eliminado para varios productos. Esta realidad permite que la calidad de los productos biológicos sea evaluada através del control de puntos críticos del proceso de producción de los mismos, eliminándose la necesidad de una rutina de control de calidad sobre el producto final.
Assuntos
Ensaio de Imunoadsorção Enzimática , Vacinas , Anticorpos , Febre Aftosa , AphthovirusRESUMO
Nucleotide sequence and phylogenetic analysis of the VP1 structural protein have been used extensively as diagnostic and epidemiological tools for foot and mouth disease virus (FMDV). In this report we have applied this methodology to the analysis of the VP1 coding sequence from FMDV strains isolated in Argentina during 1993-1994. The results demonstrated that the field isolates were related to the vaccine strains used at that time. However the involvement of the vaccine virus appeared to be different for outbreaks caused by FMD viruses type O or C. These data provide a database essential for determining the origin of new epizootics.
Assuntos
Aphthovirus/isolamento & purificação , Capsídeo/genética , Doenças dos Bovinos/virologia , Febre Aftosa/virologia , Animais , Antígenos Virais/genética , Antígenos Virais/imunologia , Aphthovirus/classificação , Aphthovirus/genética , Aphthovirus/imunologia , Argentina/epidemiologia , Sequência de Bases , Proteínas do Capsídeo , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/transmissão , Surtos de Doenças , Febre Aftosa/epidemiologia , Febre Aftosa/transmissão , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Estudos Retrospectivos , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Sorotipagem , Vacinas Virais/efeitos adversosRESUMO
Nucleotide sequence and phylogenetic analysis of the VP1 structural protein have been used extensively as diagnostic and epidemiological tools for foot and mouth disease virus (FMDV). In this report we have applied this methodology to the analysis of the VP1 coding sequence from FMDV strains isolated in Argentina during 1993-1994. The results demonstrated that the field isolates were related to the vaccine strains used at that time. However the involvement of the vaccine virus appeared to be different for outbreaks caused by FMD viruses type O or C. These data provide a database essential for determining the origin of new epizootics.