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bioRxiv · 10.1101/2020.09.21.307199

Evidence for current circulation of an ancient West Nile virus strain (NY99) in Brazil

Siconelli, M. J. L.·Jorge, D. M. d. M.·Castro-Jorge, L. A. d.·Fonseca-Junior, A. A.·Nascimento, M. L.·Floriano, V. G.·Souza, F. R. d.·Queiroz-Junior, E. M. d.·Camargos, M. F.·Costa, E. D. L.·Carvalho, A. A. B.·Fonseca, B. A. L. d.
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Abstract

IntroductionIn Brazil, West Nile virus (WNV) was first detected in 2018 from horses with neurological disease. AimHere we present the first reported case in Ceara state and complete genome sequence from an isolated in Espirito Santo state from 2019. MethodsThe virus was isolated from a horse that died with neurological signs in Espirito Santo and was sequenced by MiSeq. ResultsPhylogenetic analysis reveals that this isolate belongs to lineage 1a, clustering with NY99 strain, that disappeared from the USA since 2005. ConclusionsOur findings reinforce the hypothesis that WNV has been silently circulating in Brazil for many years.

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Siconelli, M. J. L., Jorge, D. M. d. M., Castro-Jorge, L. A. d., Fonseca-Junior, A. A., Nascimento, M. L., Floriano, V. G., Souza, F. R. d., Queiroz-Junior, E. M. d., Camargos, M. F., Costa, E. D. L., Carvalho, A. A. B., Fonseca, B. A. L. d.. 2020-09-21. Evidence for current circulation of an ancient West Nile virus strain (NY99) in Brazil. https://doi.org/10.1101/2020.09.21.307199

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