Article

Enhanced arbovirus surveillance with deep sequencing: Identification of novel rhabdoviruses and bunyaviruses in Australian mosquitoes

Department of Laboratory Medicine, University of California, 270 Masonic Avenue, San Francisco, CA 94118, USA.
Virology (Impact Factor: 3.32). 01/2014; 448:146–158. DOI: 10.1016/j.virol.2013.09.026

ABSTRACT

Viral metagenomics characterizes known and identifies unknown viruses based on sequence similarities to any previously sequenced viral genomes. A metagenomics approach was used to identify virus sequences in Australian mosquitoes causing cytopathic effects in inoculated mammalian cell cultures. Sequence comparisons revealed strains of Liao Ning virus (Reovirus, Seadornavirus), previously detected only in China, livestock-infecting Stretch Lagoon virus (Reovirus, Orbivirus), two novel dimarhabdoviruses, named Beaumont and North Creek viruses, and two novel orthobunyaviruses, named Murrumbidgee and Salt Ash viruses. The novel virus proteomes diverged by ≥50% relative to their closest previously genetically characterized viral relatives. Deep sequencing also generated genomes of Warrego and Wallal viruses, orbiviruses linked to kangaroo blindness, whose genomes had not been fully characterized. This study highlights viral metagenomics in concert with traditional arbovirus surveillance to characterize known and new arboviruses in field-collected mosquitoes. Follow-up epidemiological studies are required to determine whether the novel viruses infect humans.

Download full-text

Full-text

Available from: Eric Delwart, Aug 06, 2015
    • "2012), highlight the continued significance of bunyaviruses to human and animal health. With the application of enhanced technologies, such as next generation sequencing, additional viruses which have not been associated with disease, have been detected in or isolated from a number of arthropod species, including mosquitoes and ticks (Coffey et al., 2014; Cook et al., 2013; Warrilow et al., 2014; Zirkel et al., 2011). Of particular interest are four unusual and divergent groups of bunyaviruses recently identified in mosquitoes that do not appear to replicate in vertebrate cells (Marklewitz et al., 2011, 2015, 2013). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Insect-specific viruses belonging to significant arboviral families have recently been discovered. These viruses appear to be maintained within the insect population without the requirement for replication in a vertebrate host. Mosquitoes collected from Badu Island in the Torres Strait in 2003 were analysed for insect-specific viruses. A novel bunyavirus was isolated in high prevalence from Culex spp. The new virus, provisionally called Badu virus (BADUV), replicated in mosquito cells of both Culex and Aedes origin, but failed to replicate in vertebrate cells. Genomic sequencing revealed that the virus was distinct from sequenced bunyavirus isolates reported to date, but phylogenetically clustered most closely with recently discovered mosquito-borne, insect-specific bunyaviruses in the newly proposed Goukovirus genus. The detection of a functional furin cleavage motif upstream of the two glycoproteins in the M segment-encoded polyprotein suggests that BADUV may employ a unique strategy to process the virion glycoproteins.
    No preview · Article · Feb 2016 · Virology
  • Source
    • "whilst GGV, MPKV and SASHV have been isolated from Aedes spp. (Coffey et al., 2014;Gauci et al., 2015), suggesting that vector preference may be a contributing factor in the evolution of this group. Viral attachment to cells is mediated by interaction of the glycoproteins with vector/host receptors; this could explain why MAPV, also isolated from Anopheles spp., is more closely related to the TRUV subgroup in the polyprotein analysis (Fig. 3). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Trubanaman (TRUV) and Gan Gan (GGV) viruses are members of the tentatively assigned Mapputta group of the genus Orthobunyavirus within the family Bunyaviridae. Despite reported associations with an acute polyarthritis-like illness in Australia, TRUV and GGV have remained genetically uncharacterised. Here we report the complete genome sequences of TRUV and GGV which were originally isolated from mosquitoes in 1966 and 1970, respectively. Sequence and phylogenetic analyses indicate close relationships to other characterised viruses within the Mapputta group. These viruses exhibit the same characteristic features observed in other viruses in the group including the absence of the NSs (non-structural) ORF and an apparent absence of glycosylation sites on the Gn protein of GGV. We comment on the distribution of these viruses based on the available seroprevalence data and vector feeding preferences. The significance of this group of viruses to public health, in terms of unidentified polyarthritic disease, warrants further investigation.
    Full-text · Article · Nov 2015 · Virology Reports
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The Orthobunyavirus genus of the family Bunyaviridae is comprised of over 220 extremely diverse viral species. Members of this genus are often associated with acute febrile illness in animals and humans. As part of a longterm study of the ecology of arboviruses in the Amazon basin of Peru, we have isolated over 60 orthobunyaviruses from mosquitoes. The identification of many of these isolates by fluorescent antibody assay has been confounded by the lack of specificity of many available reagents. Therefore, we initiated genetic characterization, based on the S and M genomic segments, of selected viral isolates. Based on comparisons of the nucleotide sequences of the nucleocapsid gene, Wyeomyia, a virus in the Bunyamwera group, was the most related Orthobunyavirus species. Within the nonstructural S (NSs) open reading frame of the S segment, we found four conserved stop codons for the Peruvian isolates. Detailed comparisons of Bunyamwera, Simbu viruses, Group C viruses, and California viruses revealed all four of these NSs stop codons only appeared in Wyeomyia and the Peruvian isolates, and Guaroa conserved one of these stop codons. Such an apparent obliteration of the native NSs protein has not been described. Analysis of partial M segment amino acid sequence supports the conclusion that the viruses in this study are members of an uncharacterized orthobunyavirus group.
    Full-text · Article · Sep 2008 · Vector borne and zoonotic diseases (Larchmont, N.Y.)
Show more