Oropouche Fever: An Overview of the Epidemiological and Molecular Aspects in the Brazilian Amazon Region

Abstract

The Oropouche virus (OROV; Bunyaviridae, Orthobunyavirus) is one of the most important arbovirus that infect humans in the Amazon region causing an arboviral disease denominated Oropouche fever. Between 1961 and 2006, several outbreaks were reported in different urban areas of Para (Belem, Santa Isabel, Castanhal, Santarem, Oriximina, Serra Pelada, zone Bragantina – Igarape Acu, Maracana e Magalhaes Barata), Amazonas (Manaus e Barcelos), Acre (Xapuri), Amapa (Mazagao), Maranhao (Porto Franco), Tocantins (Tocantinopolis) and Rondonia (Ariquemes e Oro Preto D’Oeste) states. Molecular studies recently conducted have demonstrated the circulation of at least three major OROV lineages in the Amazon region (genotypes I, II and III). The genotypes I and II are more frequently detected in the western and eastern Amazon, respectively. The genotype III, previously recognized only in Panama, was recently described in Southeast region of Brazil. The association of molecular and epidemiological data has contributed substantially for the genetic characterization of OROV strains isolated during different outbreaks in the past four decades, as well as providing a better understanding regarding its molecular epidemiology in terms of emergence of new lineages and dynamic of evolution of these arboviruses in the Americas mainly in the Amazon region. This work aims to present a comprehensive review regarding the epidemiological and molecular aspects of the OROV emphasizing its geographic distribution, dynamics of the outbreaks occurred between 1961 and 2006, as well as the genotype dispersion in Brazil.