Identificação de arbovírus dengue, mayaro e oropouche em amostras com dengue negativo pela técnica NS1 no estado de Roraima, no ano de 2012

Abstract

The arboviruses are diseases caused by viruses transmitted by arthropod vector (artropod-born viruses). Transmission occurs for vertebrate hosts susceptible at the time of blood meal held by arthropod vectors or can occur between arthropods through transovarially and possibly venereal. The Amazon region has a large number of arthropod vectors (mosquitoes, sand flies, ceratopogonídeos) and wild vertebrates that coupled with the tropical climate favor the maintenance of arboviruses in nature. Inadequate management of nature through deforestation caused by the opening of roads, dams, mining and mining are some of the events responsible for outbreaks of arboviruses identified in northern Brazil. The State of Roraima is located in the extreme north of the country, with international border with Venezuela and Guyana and with the state of Amazonas and Pará. Regular studies regarding the circulation of arboviruses in the state are made just for dengue and yellow fever, which was identified in in the circulation of four dengue serotypes. The large number of reported cases of dengue laboratory diagnosis which is negative for this arbovirus demonstrated the need to expand the research to other vírus. We analyzed 150 samples with NS1 test appeared negative, from the Central Laboratory of Public Health of the State of Roraima, belonging to patients who manifested febrile syndrome in acute period of the disease (up to 5 days of onset of symptoms) and who possessed other symptoms such as arthralgia, headache, retrorbital, chills, myalgia, diarrhea, vomiting and rash. Knowing the greater sensitivity of the qPCR technique to probe the samples (150) were subjected to qPCR technique for DENV, which obtained 33 (22%) samples were positive for DEN serotypes and identified by conventional RT-PCR obtaining the following results : DENV-1 (1), DENV-2 (4), DENV-2 (3), DENV-4 (21), and obtain negative samples (3) and inconclusive (2). Subsequently 72 samples that remained negative for DENV in the qPCR were subjected to qPCR MAYV/OROV positive for obtaining MAYV (7) and OROV (13). Identification of other arboviruses circulating in the State of Roraima is necessary for knowing the viral population present and well developed mechanisms for monitoring and detection, timely entry of an emerging arbovirus responsible for a possible outbreak.