Bat Guano Virome: Predominance of Dietary Viruses from Insects and Plants plus Novel Mammalian Viruses

Blood Systems Research Institute. 270 Masonic Ave., San Francisco, CA 94118, USA.
Journal of Virology (Impact Factor: 4.44). 07/2010; 84(14):6955-65. DOI: 10.1128/JVI.00501-10
Source: PubMed


Bats are hosts to a variety of viruses capable of zoonotic transmissions. Because of increased contact between bats, humans, and other animal species, the possibility exists for further cross-species transmissions and ensuing disease outbreaks. We describe here full and partial viral genomes identified using metagenomics in the guano of bats from California and Texas. A total of 34% and 58% of 390,000 sequence reads from bat guano in California and Texas, respectively, were related to eukaryotic viruses, and the largest proportion of those infect insects, reflecting the diet of these insectivorous bats, including members of the viral families Dicistroviridae, Iflaviridae, Tetraviridae, and Nodaviridae and the subfamily Densovirinae. The second largest proportion of virus-related sequences infects plants and fungi, likely reflecting the diet of ingested insects, including members of the viral families Luteoviridae, Secoviridae, Tymoviridae, and Partitiviridae and the genus Sobemovirus. Bat guano viruses related to those infecting mammals comprised the third largest group, including members of the viral families Parvoviridae, Circoviridae, Picornaviridae, Adenoviridae, Poxviridae, Astroviridae, and Coronaviridae. No close relative of known human viral pathogens was identified in these bat populations. Phylogenetic analysis was used to clarify the relationship to known viral taxa of novel sequences detected in bat guano samples, showing that some guano viral sequences fall outside existing taxonomic groups. This initial characterization of the bat guano virome, the first metagenomic analysis of viruses in wild mammals using second-generation sequencing, therefore showed the presence of previously unidentified viral species, genera, and possibly families. Viral metagenomics is a useful tool for genetically characterizing viruses present in animals with the known capability of direct or indirect viral zoonosis to humans.

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    • "Furthermore, because horses can be hosts for zoonotic pathogens such as West Nile virus, influenza A virus, alphaviruses, Hendra virus and rabies virus (Cullinane & Newton, 2013;Johnson, 2011;Maclachlan et al., 2011;Onmaz et al., 2013;Slater, 2013), equine infectious diseases are also relevant from a human public health perspective. Viral metagenomics has recently been used in numerous animal virus discoveries (Cann et al., 2005;Chandriani et al., 2013;Delwart, 2012;Li et al., 2010b;Ng et al., 2014;Scheel et al., 2015;Shan et al., 2011;Zhang et al., 2014). A deep sequencing approach was used here to characterize eukaryotic viral sequences in a variety of biological sample types from horses with diseases of suspected viral aetiology. "
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