Dengue virus serotypes 1-4 phylogeography in São Paulo state: a retrospective study from 1991 until 2016

Abstract

Dengue is the most important arbovirus in the world, with a great impact on World Public Health thanks to its morbidity and lethality in some cases. It is caused by dengue serotypes 1-4, viruses belonging to the Flaviviridae family, genus Flavivirus, transmitted in Brazil by the vector Aedes aegypti. In areas considered endemic for the virus, different serotypes and genotypes may co-circulate. Each of these genotypes can show different degrees of virulence, as well as different genetic lineages. The circulation dynamics of these serotypes in the human population is complex and during the circulation of a serotype, for long periods, it tends to disappear due to the development of immunity in the population. Despite the large amount of laboratory confirmation of human cases, the pattern of viral movements over time in the state of São Paulo is still poorly understood, due to the existence of different genotypes and/or lineages. Thus, the present project aims, through complete genome sequencing of dengue viruses isolated in cell cultures and detected by real-time RT-PCR (RT-qPCR) at the Instituto Adolfo Lutz in the period from 1991 to 2016, to understand the dynamics of the spread of the different serotypes of the virus and their genotypes, also identifying possible virulence markers from severe cases (AU)