PLoS ONE (Jan 2019)

Molecular characterization of viruses associated with encephalitis in São Paulo, Brazil.

  • Jerenice E Ferreira,
  • Suzete C Ferreira,
  • Cesar Almeida-Neto,
  • Anna S Nishiya,
  • Cecilia S Alencar,
  • Gisele R Gouveia,
  • Helio Caiaffa-Filho,
  • Helio Gomes,
  • Raimunda Telma de Macedo Santos,
  • Steven S Witkin,
  • Alfredo Mendrone-Junior,
  • Ester C Sabino

DOI
https://doi.org/10.1371/journal.pone.0209993
Journal volume & issue
Vol. 14, no. 1
p. e0209993

Abstract

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The objective of this study was to characterize the prevalence of viral encephalitis due to arbovirus infection of the Togaviridae and Flaviviridae families in São Paulo, Brazil. A total of 500 cerebrospinal fluid (CSF) samples collected between August 2012 and January 2013, from patients with symptoms of acute encephalitis were analyzed. Findings suggestive of viral encephalitis-elevations in cell concentration, glucose and total protein-were observed in 234 (46.8%) samples, designated as Group 1. The remaining 266 samples comprised Group 2. All samples were tested for Flaviviruses (dengue virus 1, 2, 3 and 4, yellow fever virus and West Nile virus), Alphavirus (NS5 region) and enterovirus by RT- PCR and for herpesviruses and enteroviruses using CLART-Entherpex. A presumptive viral etiological agent was detected in 26 samples (5.2%), 18 (8.0%) in Group 1 and 8 (3.0%) in Group 2. In Group 1 human herpesviruses were detected in 9 cases, enteroviruses in 7 cases, dengue viruses (DENV) in 2 CSFs and St. Louis encephalitis virus (SLEV) in one case. In Group 2 there were 3 CSFs positive for human herpesviruses, 2 for enteroviruses, 2 for DENV and 1 for SLEV. Detection of arboviruses, even though present in a minority of infected patients, identifies these viruses as a probable etiological agent of encephalitis. This is of special concern in regions where this class of viruses is endemic and has been linked to other recent epidemics.