Browsing by Author "Tesh, Robert B."

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    Isolation of a novel insect-specific flavivirus with immunomodulatory effects in vertebrate systems
    Auguste, A. Jonathan; Langsjoen, Rose M.; Porier, Danielle L.; Erasmus, Jesse H.; Bergren, Nicholas A.; Bolling, Bethany G.; Luo, Huanle; Singh, Ankita; Guzman, Hilda; Popov, Vsevolod L.; da Rosa, Amelia P. A. Travassos; Wang, Tian; Kang, Lin; Allen, Irving C.; Carrington, Christine V. F.; Tesh, Robert B.; Weaver, Scott C. (2021-10)
    We describe the isolation and characterization of a novel insect-specific flavivirus (ISFV), tentatively named Aripo virus (ARPV), that was isolated from Psorophora albipes mosquitoes collected in Trinidad. The ARPV genome was determined and phylogenetic analyses showed that it is a dual host associated ISFV, and clusters with the main mosquito-borne flaviviruses. ARPV antigen was significantly cross-reactive with Japanese encephalitis virus serogroup antisera, with significant cross-reactivity to Ilheus and West Nile virus (WNV). Results suggest that ARPV replication is limited to mosquitoes, as it did not replicate in the sandfly, culicoides or vertebrate cell lines tested. We also demonstrated that ARPV is endocytosed into vertebrate cells and is highly immunomodulatory, producing a robust innate immune response despite its inability to replicate in vertebrate systems. We show that prior infection or coinfection with ARPV limits WNV-induced disease in mouse models, likely the result of a robust ARPV-induced type I interferon response.
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    Large scale complete genome sequencing and phylodynamic analysis of eastern equine encephalitis virus reveal source-sink transmission dynamics in the United States
    Tan, Yi; Lam, Tommy Tsan-Yuk; Heberlein-Larson, Lea A.; Smole, Sandra C.; Auguste, A. Jonathan; Hennigan, Scott; Halpin, Rebecca A.; Fedorova, Nadia; Puri, Vinita; Stockwell, Timothy B.; Shilts, Meghan H.; Andreadis, Theodore G.; Armstrong, Philip M.; Tesh, Robert B.; Weaver, Scott C.; Unnasch, Thomas R.; Ciota, Alexander T.; Kramer, Laura D.; Das, Suman R. (American Society for Microbiology, 2018-04-04)
    Eastern equine encephalitis virus (EEEV) has a high case-fatality rate in horses and humans, and Florida has been hypothesized to be the source of EEEV epidemics for the northeastern United States. To test this hypothesis, we sequenced complete genomes of 433 EEEV strains collected within the United States from 1934 to 2014. Phylogenetic analysis suggested EEEV evolves relatively slowly and that transmission is enzootic in Florida, characterized by higher genetic diversity and long-term local persistence. In contrast, EEEV strains in New York and Massachusetts were characterized by lower genetic diversity, multiple introductions, and shorter local persistence. Our phylogeographic analysis supported a source-sink model in which Florida is the major source of EEEV compared to the other localities sampled. In sum, this study revealed the complex epidemiological dynamics of EEEV in different geographic regions in the United States and provided general insights into the evolution and transmission of other avian mosquito-borne viruses in this region.
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    Phylogenetic characterization of Orthobunyaviruses isolated from Trinidad shows evidence of natural reassortment
    Foster, Jerome E.; Lopez, Krisangel; Eastwood, Gillian; Guzman, Hilda; Carrington, Christine V. F.; Tesh, Robert B.; Auguste, A. Jonathan (Springer, 2023-02)
    The genus Orthobunyavirus is a diverse group of viruses in the family Peribunyaviridae, recently classified into 20 serogroups, and 103 virus species. Although most viruses within these serogroups are phylogenetically distinct, the absence of complete genome sequences has left several viruses incompletely characterized. Here we report the complete genome sequences for 11 orthobunyaviruses isolated from Trinidad, French Guiana, Guatemala, and Panama that were serologically classified into six serogroups and 10 species. Phylogenetic analyses of these 11 newly derived sequences indicate that viruses belonging to the Patois, Capim, Guama, and Group C serocomplexes all have a close genetic origin. We show that three of the 11 orthobunyaviruses characterized (belonging to the Group C and Bunyamwera serogroups) have evidence of histories of natural reassortment through the M genome segment. Our data also suggests that two distinct lineages of Group C viruses concurrently circulate in Trinidad and are transmitted by the same mosquito vectors. This study also highlights the importance of complementing serological identification with nucleotide sequencing when characterizing orthobunyaviruses.