Potential of Ilheus virus to emerge

Plante, K. S.; Plante, J. A.; Azar, S. R.; Shinde, D. P.; Scharton, D.; Versiani, A. F.; Oliveira da Silva, N. I.; Strange, T.; Sacchetto, L.; Fokam, E. B.; Rossi, S. L.; Weaver, S.; Marques, R. E.; Nogueira, M. L.; Vasilakis, N.

doi:10.1101/2023.09.08.556909

bioRxiv · 10.1101/2023.09.08.556909

Potential of Ilheus virus to emerge

Plante, K. S.·Plante, J. A.·Azar, S. R.·Shinde, D. P.·Scharton, D.·Versiani, A. F.·Oliveira da Silva, N. I.·Strange, T.·Sacchetto, L.·Fokam, E. B.·Rossi, S. L.·Weaver, S.·Marques, R. E.·Nogueira, M. L.·Vasilakis, N.

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Abstract

Ilheus virus (ILHV)(Flaviviridae: Orthoflavivirus) is an arthropod-borne virus (arbovirus) endemic to Central and South America and the Caribbean. First isolated in 1944, most of our knowledge derives from surveillance and seroprevalence studies. These efforts have detected ILHV in a broad range of mosquito and vertebrate species, including humans, but laboratory investigations of pathogenesis and vector competence have been lacking. Here, we develop several immune intact murine models that closely recapitulate human neuroinvasive disease with strain- and age-specific virulence, as well as a uniformly lethal immunocompromised model. Replication kinetics in several vertebrate and invertebrate cell lines demonstrate that ILHV is capable of replicating to high titers in a wide variety of potential host and vector species. Lastly, vector competence studies provide strong evidence for efficient infection of and potential transmission by Aedes species mosquitoes, despite ILHVs phylogenetically clustering with Culex vectored flaviviruses, suggesting ILHV is poised for emergence in the neotropics. TeaserMurine models of ILHV mimic human disease, and Aedes species of mosquitoes are highly susceptible to infection and dissemination.

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Plante, K. S., Plante, J. A., Azar, S. R., Shinde, D. P., Scharton, D., Versiani, A. F., Oliveira da Silva, N. I., Strange, T., Sacchetto, L., Fokam, E. B., Rossi, S. L., Weaver, S., Marques, R. E., Nogueira, M. L., Vasilakis, N.. 2023-09-09. Potential of Ilheus virus to emerge. https://doi.org/10.1101/2023.09.08.556909

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