15 research outputs found
Serological study of vaccinia virus reservoirs in areas with and without official reports of outbreaks in cattle and humans in São Paulo, Brazil
Vaccinia virus (VACV), the etiological agent of an exanthematic disease, has been associated with several bovine outbreaks in Brazil since the end of the global vaccination campaign against smallpox. It was previously believed that the vaccine virus used for the WHO global campaign had adapted to an unknown wild reservoir and was sporadically re-emerging in outbreaks in cattle and milkers. At present, it is known that Brazilian VACV is phylogenetically different from the vaccinia virus vaccinal strain, but its origin remains unknown. This study assessed the seroprevalence of orthopoxviruses in domestic and wild animals and farmers from 47 farms in three cities in the southwest region of the state of São Paulo with or without official reports of outbreaks in cattle or humans. Our data indicate a low seroprevalence of antibodies in wild animals and raise interesting questions about the real potential of wild rodents and marsupials as VACV reservoirs, suggesting other routes through which VACV can be spread
Serological study of vaccinia virus reservoirs in areas with and without official reports of outbreaks in cattle and humans in São Paulo, Brazil
Rough virulent strain of Brucella ovis induces pro- and anti-inflammatory cytokines in reproductive tissues in experimentally infected rams
Análise filogenética correlacionada com a distribuição do vírus rábico em quirópteros naturalmente infectados
Morcegos vêm recebendo crescente importância em Saúde Pública, pois são os principais reservatórios para a raiva em diversas partes do mundo. Pouco se conhece a respeito da distribuição do vírus rábico em tecidos e órgãos não nervosos. O objetivo deste estudo foi avaliar a distribuição do vírus rábico em órgãos e tecidos de quirópteros naturalmente infectados de diferentes hábitos alimentares, e avaliar a existência de alguma possível correlação com a filogenia das amostras. Foram utilizados 26 morcegos previamente diagnosticados positivos para raiva pelos métodos padrão, sendo coletado cérebro, glândulas salivares, pulmão, coração, fígado, baço, estômago, intestinos, rins, bexiga, gordura interescapular e fezes. As amostras foram submetidas à extração do material genético e submetidas à reação de RT-PCR com iniciadores específicos para o gene N. As amostras que resultaram negativas na primeira reação foram submetidas a uma segunda amplificação (hemi-nested PCR). Os produtos amplificados foram submetidos ao sequenciamento genético e as sequências alinhadas com sequências homólogas obtidas do GenBank para construção da árvore filogenética. Os resultados demonstraram uma ampla distribuição do vírus em órgãos e tecidos dos morcegos, não sendo possível correlacionar com a espécie e tão pouco com a linhagem viral encontrada. O maior percentual de positividade foi encontrado em cérebro e glândula salivar e a técnica de heminested PCR demonstrou ter maior sensibilidade na detecção do vírus rábico nas amostras estudadas. Na análise filogenética observou-se o agrupamento das amostras de acordo com as espécies, confirmando a existência de linhagens gênero específicasBats have been assigned an increasing importance in Public Health as these are the main rabies reservoirs in many parts of the world. Little is known about the distribution of rabies virus in non-nervous tissues and organs. The aim of this study was to evaluate the distribution of rabies virus in organs and tissues of naturally infected bats with different feeding habits, and evaluate the existence of any possible correlation with the phylogeny of the samples. 26 bats previously diagnosed as positive for rabies by standard methods were used; the brain, salivary glands, lung, heart, liver, spleen, stomach, intestine, kidneys, urinary bladder, interscapular fat and feces were collected. The genetic material were extracted and submited to RT-PCR reaction with specific primers for the N gene. The samples that were negative in the first reaction underwent a second amplification (hemi-nested PCR). The amplified products were subjected to genetic sequencing and the sequences aligned with homologous sequences obtained from GenBank for phylogenetic tree construction. The results showed a wide distribution of virus in organs and tissues of bats, it was not possible to correlate the viral distribuition with the species nor with the viral strain found. The highest percentage of positivity was found in brain and salivary glands and the technique of heminested PCR demonstrated to have a greater sensitivity for detection of rabies virus in the studied samples. The phylogenetic analysis showed the clustering of samples according to the species, confirming the existence of genus specific lineagesCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Persistence and dissemination of Vaccinia virus zoonotic infection in central west region of São Paulo State - Brazil
The aim of this study was to describe the persistence and dissemination of Vaccinia Virus (VACV) in Central West region of São Paulo State-Brazil and the zoonotic character of the disease. The work suggests viral circulation and maintenance of VACV by possible wildlife reservoir.O objetivo deste estudo foi descrever a persistência, a disseminação e o caráter zoonótico do vírus Vaccinia (VACV) na região Centro-Oeste do Estado de São Paulo-Brasil. O trabalho sugere a circulação viral e a manutenção do VACV por um possível reservatório em animais silvestres
Detecção de Brucella spp. em leite bovino não pasteurizado através da Reação de Cadeia pela Polimerase (PCR)
A brucelose é uma importante zoonose causada por bactérias do gênero Brucella. O homem é infectado pelo contato com as secreções reprodutivas como placenta, lóquios placentários, sêmen e secreções penianas de animais infectados ou pelo consumo de leite e derivados não pasteurizados. Com o objetivo de pesquisar a presença da bactéria no leite, foram avaliadas, através da técnica da reação em cadeia da polimerase (PCR), 30 amostras de leite cru comercializadas clandestinamente na região de Botucatu, São Paulo, bem como 50 amostras de leite entregues em laticínio, previamente à pasteurização. Das 80 amostras analisadas pela técnica de PCR, 10 (12,5%) foram positivas e 70 (87,5%) negativas. Dentre as amostras positivas, 5 amostras (16,6%) eram provenientes de comerciantes ilegais e outras 5 amostras (10%) foram obtidas no laticínio. A positividade para Brucella spp. demonstra que o patógeno se encontra presente de forma importante na região de Botucatu, São Paulo, e que o risco associado à saúde pública devido à comercialização de produtos clandestinos sem prévia pasteurização é real
Ribavirin has an in vitro antiviral effect in rabies virus infected neuronal cells but fails to provide benefit in experimental rabies in mice
Objectives: The nucleoside analog ribavirin is one of the antiviral drugs recommended in the management of several viral infections in humans. Although ribavirin has been used in rabies treatment, its efficacy has not been formally proven. The objectives were to study the effect of ribavirin on rabies virus (RABV) infection in neuronal cultures, to analyze whether orally-given ribavirin activates an innate immune response in the brain and whether ribavirin confers protection against brain infection in a model of experimental rabies in mice. Design: The effect of ribavirin on RABV multiplication was evaluated in vitro in both fibroblast (BSRT7) and neuroblastoma cell lines (SKN-SH) and also in vivo using an experimental rabies post-exposure treatment in C57BL6 mice, which were inoculated with different street RABV strains in different doses. Results: Ribavirin has a significant antiviral effect in both cell cultures. Orally-given ribavirin triggers a transient innate immune response in the mouse brain. Post-exposure oral treatment with ribavirin in mice provides no benefit against rabies Conclusion: Despite the significant effects of ribavirin on RABV multiplication in vitro, and the induction of an innate immune response in the brain, post-exposure oral treatment with ribavirin provides no benefit as a treatment for rabies.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Evaluation of short-interfering RNAs treatment in experimental rabies due to wild-type virus
We have evaluated the efficacy of short-interfering RNAs targeting the nucleoprotein gene and also the brain immune response in treated and non-treated infected mice. Mice were inoculated with wild-type virus, classified as dog (hv2) or vampire bat (hv3) variants and both groups were treated or leaved as controls. No difference was observed in the lethality rate between treated and non-treated groups, although clinical evaluation of hv2 infected mice showed differences in the severity of clinical disease (p = 0.0006). Evaluation of brain immune response 5 days post-inoculation in treated hv2 group showed no difference among the analyzed genes, whereas after 10 days post-inoculation there was increased expression of 2′,5′-oligoadenylate synthetase 1, tumor necrosis factor alpha, interleukin 12, interferon gamma, and C-X-C motif chemokine 10 associated with higher expression of N gene in the same period (p < 0.0001). In hv2 non-treated group only higher interferon beta expression was found at day 5. The observed differences in results of the immune response genes between treated and non-treated groups is not promising as they had neither impact on mortality nor even a reduction in the expression of N gene in siRNA treated animals. This finding suggests that the use of pre-designed siRNA alone may not be useful in rabies treatment. Keywords: Rabies, Dog virus, Bat virus, siRN
Mortalidade embrionária/fetal e abortos em suínos do Brasil
The objective was to evaluate the major infectious etiologies for embrionary/fetal mortality and abortion in pigs. Brazil is the world's fourth producer and third largest pork exporter. The causes of infectious abortion in swine are of the order of 40%, where the infections are the most important causes of reproductive disorders such as absorption, mummification, abortions, stillbirth and infertility. Due to high technification of swine in Brazil, a high density is found in animal farms, which lead to the virus are the main agents of reproductive disorders.O objetivo deste trabalho foi levantar as principais causas infecciosas de mortalidade embrionária/fetal e abortos em suínos. O Brasil é o quarto produtor mundial de carne suína e o terceiro maior exportador. As causas infecciosas de problemas reprodutivos na suinocultura são da ordem de 40%, onde as infecções são as causas mais importantes de reabsorção, mumificação, abortamentos, natimortos e infertilidade. Devido à alta tecnificação da suinocultura no Brasil, uma alta densidade animal é encontrada nas granjas, o que levam aos vírus serem os principais agentes infecciosos envolvidos