Silent circulation of the Saint Louis Encephalitis virus among humans and equids, southeast Brazil

• Autor(a) principal: Galileu Barbosa Costa
• Data de Publicação: 2019
• Outros Autores: Danilo Bretas de Oliveira, Betania Paiva Drumond, Erna Geessien Kroon, Giliane de Souza Trindade, Paula Eillany Silva Marinho, Ana Paula Pessoa Vilela, Ana Teresa Saraiva Silva, Ana Paula Correia Crispim, Iara Apolinário Borges, Ana Gabriella Stoffella Dutra, Zélia Inês Portela Lobato, Jenner Karlison Pimenta dos Reis
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFMG
• Texto Completo: https://doi.org/10.3390/v11111029; http://hdl.handle.net/1843/61652; https://orcid.org/0000-0001-7360-6722; https://orcid.org/0000-0002-3566-2878; https://orcid.org/0000-0002-4049-4055; https://orcid.org/0000-0003-2721-3826; https://orcid.org/0000-0003-0785-4298; https://orcid.org/0000-0001-9030-0688; https://orcid.org/0000-0002-3127-2266; https://orcid.org/0000-0003-1466-5575; https://orcid.org/0000-0002-4985-2840; https://orcid.org/0000-0002-9399-3691; https://orcid.org/0000-0003-0395-358X
• topic: Saint Louis encephalitis virus; Seroprevalence; Epidemiology; Asymptomatic cases; Public health burden; Vírus da encefalite de St. Louis; Estudos soroepidemiológicos; Epidemiologia; Doenças assintomáticas; Saúde pública

Saint Louis encephalitis virus (SLEV) is a mosquito-borne flavivirus that occurs throughout the Americas, and is considered a public health threat. In Brazil, SLEV has been detected from human cases associated with dengue-like disease, but no neurological symptoms were reported. Furthermore, the epidemiology of SLEV in human populations is still poorly explored in the country. We reported serological and molecular detection of SLEV in a healthy population of equids and humans from rural areas in Southeast Brazil. A plaque reduction neutralization test was applied, and neutralizing antibodies were detected in 11 individuals (4.6%) and 60 horses (21.5%). A qPCR targeting the 5′UTR region and reverse transcription-PCR (RT-PCR) targeting the non-structural protein (NS5) gene were performed and three individuals tested positive in both assays. Subsequent phylogenetic analysis confirmed SLEV circulation and its findings suggest the occurrence of an asymptomatic or subclinical presence in human and animal cases, correlating with the risks for outbreaks and consequently burden of SLEV infections to public health. Preventive strategies should include improved surveillance in regions with a high probability of SLEV occurrence, improvement in diagnostic methods, and evaluation of exposure/risk factors that can favor SLEV emergence.