Detecção molecular de arbovirus emergentes: West Nile, Saint Louis e Mayaro

Abstract

Arboviruses are viral diseases transmitted by arthropod vectors, especially mosquitoes of the Culex and Aedes genus. These diseases are spread across the world and have major impacts on health and the economy. In Brazil there are several arboviruses in circulation, such as Zika (ZIKV) and dengue (DENV). Some arboviruses are considered emerging, such as mayaro (MAYV), Saint Louis encephalitis virus (SLEV) and West Nile virus (WNV). Despite having been detected in Brazil and having the potential to cause epidemics, these arboviruses have not yet spread within Brazilian territory. Due to geographic and social characteristics, Brazil presents the ideal environment for the dispersion of arboviruses. In this context, real-time PCR assays (qPCR) were developed to detect SLEV and MAYV viruses. To standardize the qPCR, a plasmid containing the sequences of these viruses was used and, from these sequences, primers and probes were designed. For the MAYV assay it was possible to obtain 96.39% efficiency and, with regard to sensitivity, detection of one single viral RNA copy. As for the SLEV assay, an efficiency of 104.67% and sensitivity for detecting one single viral RNA copy were obtained. Regarding specificity, both assays were specific for the virus of interest. The standardized assays for SLEV and MAYV showed efficiency, specificity and sensitivity within the standards determined for qPCR, being suitable for use in routine laboratory diagnostics.