This paper describes the construction and characterization of a Brazilian strain of bovine herpesvirus type 1.2a (BoHV-1.2a) with a deletion of the glycoprotein E (gE) gene. The deletion was introduced by cotransfection of a deletion fragment containing the 5´and 3´gE flanking regions and genomic DNA of wild type BoHV-1 into bovine cells. Isolation of gE deletion mutant was performed by immunoperoxidase staining with an anti-gE monoclonal antibody. Viral clones were plaque purified and further examined by restriction endonuclesase digestion and Southern blot hybridization. This gE deletion mutant will be evaluated as a vaccinal virus, in order to determine its potential use for a differential vaccine.
, was designed as a vaccinal strain for differential vaccines, allowing the distinction between vaccinated and naturally infected cattle. In order to determine the safety and efficacy of this candidate vaccine virus, a group of calves was inoculated with 265gE -. The virus was detected in secretions of inoculated calves to lower titres and for a shorter period than the parental virus inoculated in control calves. Twenty one days after inoculation, the calves were challenged with the wild type parental virus. Only mild signs of infection were detected on vaccinated calves, whereas nonvaccinated controls displayed intense rhinotracheitis and shed virus for longer and to higher titres than vaccinated calves. Six months after vaccination, both vaccinated and control groups were subjected to reactivation of potentially latent virus. The mutant 265gE -could not be reactivated from vaccinated calves. The clinical signs observed, following the reactivation of the parental virus, were again much milder on vaccinated than on non-vaccinated calves. Moreover, parental virus shedding was considerably reduced on vaccinated calves at reactivation. In view of its attenuation, immunogenicity and protective effect upon challenge and reactivation with a virulent BHV-1, the mutant 265gE -was shown to be suitable for use as a BHV-1 differential vaccine virus.INDEX TERMS: BHV-1, differential vaccine, gE deletion, IBR.
The study aimed to examine the capacity of two bovine herpesvirus type 1 (BHV-1) isolates of different subtypes (EVI 123/96, BHV-1.1; SV265/98, BHV-1.2a) to induce respiratory disease in calves. These two isolates are representative of the BHV-1 subtypes prevalent in Brazil. Viral subtypes were confirmed by monoclonal antibody analysis and by restriction enzyme digestion of viral genomes. The viruses were inoculated intranasally into seven 3 months old calves (four with BHV-1.1, three with BHV-1.2a). Three other calves of identical age and condition were kept as uninfected controls. In both groups of infected calves, the clinical signs observed were consistent with typical infectious bovine rhinothracheitis (IBR), including pyrexia, apathy, anorexia, nasal and ocular mucopurulent discharges, erosions on the nasal mucosa, conjunctivitis, lachrymation, redness of nasal mucosa, dyspnoea, coughing, tracheal stridor and enlargement of retropharingeal, submandibular and cervical lymphnodes. No significant differences were observed between the clinical scores attributed to both groups. Virus shedding in nasal and ocular secretions were also similar, apart from a significant difference in nasal virus shedding on day 1 to 3 post-inoculation, which was higher for BHV-1.1 than for BHV-1.2a. Following corticosteroid induced reactivation of the latent infection, recrudescence of clinical signs was also observed, with no significant differences on both groups. It was concluded that both subtypes BHV-1.1 and BHV-1.2a were able to induce clinically undistinguishable respiratory disease in calves, either subsequent to a primary infection or following reactivation.
Here we report the presence and expression levels of the vanC 1 and vanC 2/3 genes in vancomycin-susceptible strains of Enterococcus faecalis. The vanC 1 and vanC 2/3 genes were located in the plasmid DNA and on the chromosome, respectively. Specific mRNA of the vanC 1 gene was detected in one of these strains. Additionally, analysis of the vanC gene sequences showed that these genes are related to the vanC genes of Enterococcus gallinarum and Enterococcus casseliflavus. The presence of vanC genes is useful for the identification of E. gallinarum and E. casseliflavus. Moreover, this is the first report of vanC mRNA in E. faecalis.
É descrito o isolamento do vírus Parainfluenza bovino tipo 3 (bPI-3) a partir de secreções nasais coletadas de um bovino com infecção respiratória. A identificação do agente foi realizada através de isolamento em cultivo celular e confirmada por testes de hemaglutinação, inibição da hemaglutinação, hemadsorção e imunofluorescência direta. Este é o primeiro registro do isolamento do vírus no Rio Grande do Sul.
Sapajus nigritus are non-human primates which are widespread in South America. They are omnivores and live in troops of up to 40 individuals. The oral cavity is one of the main entry routes for microorganisms, including viruses. Our study proposed the identification of viral sequences from oral swabs collected in a group of capuchin monkeys (n = 5) living in a public park in a fragment of Mata Atlantica in South Brazil. Samples were submitted to nucleic acid extraction and enrichment, which was followed by the construction of libraries. After high-throughput sequencing and contig assembly, we used a pipeline to identify 11 viral families, which are Herpesviridae, Parvoviridae, Papillomaviridae, Polyomaviridae, Caulimoviridae, Iridoviridae, Astroviridae, Poxviridae, and Baculoviridae, in addition to two complete viral genomes of Anelloviridae and Genomoviridae. Some of these viruses were closely related to known viruses, while other fragments are more distantly related, with 50% of identity or less to the currently available virus sequences in databases. In addition to host-related viruses, insect and small vertebrate-related viruses were also found, as well as plant-related viruses, bringing insights about their diet. In conclusion, this viral metagenomic analysis reveals, for the first time, the profile of viruses in the oral cavity of wild, free ranging capuchin monkeys.
RESUMOProvavelmente todas as espécies animais de sangue quente são passíveis de serem infectadas pelo vírus da raiva (VR). No entanto, a maioria dessas espécies, quando infectadas, tornam-se hospedeiros finais do agente, pois a infecção resulta em morte e não ocorre disseminação do mesmo para novos hospedeiros. Para garantir sua perpetuação na natureza, o VR adaptou-se a determinadas espécies, denominadas "hospedeiros naturais", as quais servem como reservatórios do vírus. Durante esse processo de adaptação, modificações genômicas e antigênicas são geradas, originando as chamadas "variantes" do VR. Estas por vezes apresentam alterações que podem ser utilizadas como marcadores epidemiológicos, permitindo, por exemplo, a identificação da espécie fonte de infecção ou de variantes associadas a determinados nichos ecológicos. Nesta breve revisão são apresentados dados sobre o VR e sobre a ocorrência de variantes no Brasil, com ênfase nos achados de uma parcela dos inúmeros estudos realizados sobre o tema. São também apresentados e discutidos dados epidemiológicos sobre a situação da raiva no País nos últimos dez anos (1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006), salientando-se a marcada redução no número de casos de raiva urbana em cães e em humanos, estes últimos infelizmente compensados por um aumento no número de casos humanos associados a contatos com morcegos hematófagos no triênio 2004-2006. ABSTRACTProbably all warm blooded animals are susceptible to rabies virus (RV) infections. However, most of these species will end up as terminal hosts for the virus, since a fatal outcome is the rule and usually no virus dissemination from such hosts occur. Nevertheless, in nature, RV has become adapted to certain species, referred to as "natural hosts", which act as reservoirs for the virus. During the process of virus adaptation to such hosts, genomic and eventually antigenic modifications are generated that can be used as markers which may help to identify the natural host which acted as source of infection, along with other characteristics peculiar to such modified viruses, denominated RV "variants". Such variants may bear alterations that can be used as epidemiological markers, allowing for instance the identification of the source of infection or the establishment of associations between a particular variant and a defined ecological niche. In this brief review, some of the recent data on the virus and the occurrence of variants are presented, with emphasis on the findings of a parcel of the various studies on the subject that have been carried out in Brazil. Epidemiologic data on reported cases of rabies in the country in the last ten years (1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006) are presented and discussed, highlighting the marked decrease in the numbers of urban cases of rabies in dogs and humans, what was unfortunately compensated by an increase in the number of human cases associated to vampire bat transmission in the trienium 2004-2006.
The family Mimiviridae, comprised by giant DNA viruses, has been increasingly studied since the isolation of the Acanthamoeba polyphaga mimivirus (APMV), in 2003. In this work, we describe the genome analysis of two new mimiviruses, each isolated from a distinct Brazilian environment. Furthermore, for the first time, we are reporting the genomic characterization of mimiviruses of group C in Brazil (Br-mimiC), where a predominance of mimiviruses from group A has been previously reported. The genomes of the Br-mimiC isolates Mimivirus gilmour (MVGM) and Mimivirus golden (MVGD) are composed of double-stranded DNA molecules of ∼1.2 Mb, each encoding more than 1,100 open reading frames. Genome functional annotations highlighted the presence of mimivirus group C hallmark genes, such as the set of seven aminoacyl-tRNA synthetases. However, the set of tRNA encoded by the Br-mimiC was distinct from those of other group C mimiviruses. Differences could also be observed in a genome synteny analysis, which demonstrated the presence of inversions and loci translocations at both extremities of Br-mimiC genomes. Both phylogenetic and phyletic analyses corroborate previous results, undoubtedly grouping the new Brazilian isolates into mimivirus group C. Finally, an updated pan-genome analysis of genus Mimivirus was performed including all new genomes available until the present moment. This last analysis showed a slight increase in the number of clusters of orthologous groups of proteins among mimiviruses of group A, with a larger increase after addition of sequences from mimiviruses of groups B and C, as well as a plateau tendency after the inclusion of the last four mimiviruses of group C, including the Br-mimiC isolates. Future prospective studies will help us to understand the genetic diversity among mimiviruses.
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