RESUMO
Encephalitis is a major cause of death worldwide. Although >100 pathogens have been identified as causative agents, the pathogen is not determined for up to 75% of cases. This diagnostic failure impedes effective treatment and underscores the need for better tools and new approaches for detecting novel pathogens or determining new manifestations of known pathogens. Although astroviruses are commonly associated with gastroenteritis, they have not been associated with central nervous system disease. Using unbiased pyrosequencing, we detected an astrovirus as the causative agent for encephalitis in a 15-year-old boy with agammaglobulinemia; several laboratories had failed to identify the agent. Our findings expand the spectrum of causative agents associated with encephalitis and highlight unbiased molecular technology as a valuable tool for differential diagnosis of unexplained disease.
Assuntos
Agamaglobulinemia/complicações , Infecções por Astroviridae/diagnóstico , Encefalite Viral/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/complicações , Mamastrovirus/isolamento & purificação , Adolescente , Agamaglobulinemia/genética , Infecções por Astroviridae/etiologia , Proteínas do Capsídeo/análise , Proteínas do Capsídeo/genética , Encefalite Viral/etiologia , Evolução Fatal , Lobo Frontal/patologia , Lobo Frontal/virologia , Humanos , Imuno-Histoquímica , Masculino , Mamastrovirus/genética , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , Análise de Sequência de RNARESUMO
K13965, an uncharacterized virus, was isolated in 1993 from Anopheles annulipes mosquitoes collected in the Kimberley region of northern Western Australia. Here, we report its genomic sequence, identify it as a rhabdovirus, and characterize its phylogenetic relationships. The genome comprises a P' (C) and SH protein similar to the recently characterized Tupaia and Durham viruses, and shows overlap between G and L genes. Comparison of K13965 genome sequence to other rhabdoviruses identified K13965 as a strain of the unclassified Australian Oak Vale rhabdovirus, whose complete genome sequence we also determined. Phylogenetic analysis of N and L sequences indicated genetic relationship to a recently proposed Sandjima virus clade, although the Oak Vale virus sequences form a branch separate from the African members of that group.
Assuntos
Anopheles/virologia , Genoma Viral , Rhabdoviridae/genética , Rhabdoviridae/isolamento & purificação , Análise de Sequência de DNA , Animais , Análise por Conglomerados , Feminino , Dados de Sequência Molecular , Filogenia , RNA Viral/genética , Proteínas Virais/genética , Austrália OcidentalRESUMO
Characterization of arboviruses at the interface of pristine habitats and anthropogenic landscapes is crucial to comprehensive emergent disease surveillance and forecasting efforts. In context of a surveillance campaign in and around a West African rainforest, particles morphologically consistent with rhabdoviruses were identified in cell cultures infected with homogenates of trapped mosquitoes. RNA recovered from these cultures was used to derive the first complete genome sequence of a rhabdovirus isolated from Culex decens mosquitoes in Côte d'Ivoire, tentatively named Moussa virus (MOUV). MOUV shows the classical genome organization of rhabdoviruses, with five open reading frames (ORF) in a linear order. However, sequences show only limited conservation (12-33% identity at amino acid level), and ORF2 and ORF3 have no significant similarity to sequences deposited in GenBank. Phylogenetic analysis indicates a potential new species with distant relationship to Tupaia and Tibrogargan virus.
Assuntos
Culex/virologia , Rhabdoviridae/classificação , Rhabdoviridae/isolamento & purificação , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Sequência de Bases , Análise por Conglomerados , Côte d'Ivoire , Feminino , Ordem dos Genes , Genes Virais , Genoma Viral , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , Rhabdoviridae/genética , Análise de Sequência de DNA , Homologia de Sequência de AminoácidosRESUMO
Bats are reservoirs for emerging zoonotic viruses that can have a profound impact on human and animal health, including lyssaviruses, filoviruses, paramyxoviruses, and severe acute respiratory syndrome coronaviruses (SARS-CoVs). In the course of a project focused on pathogen discovery in contexts where human-bat contact might facilitate more efficient interspecies transmission of viruses, we surveyed gastrointestinal tissue obtained from bats collected in caves in Nigeria that are frequented by humans. Coronavirus consensus PCR and unbiased high-throughput pyrosequencing revealed the presence of coronavirus sequences related to those of SARS-CoV in a Commerson's leaf-nosed bat (Hipposideros commersoni). Additional genomic sequencing indicated that this virus, unlike subgroup 2b CoVs, which includes SARS-CoV, is unique, comprising three overlapping open reading frames between the M and N genes and two conserved stem-loop II motifs. Phylogenetic analyses in conjunction with these features suggest that this virus represents a new subgroup within group 2 CoVs.