The dengue virus is classified as an arbovirus and remains in nature by multiplying in hematophagous mosquitoes of the Aedes genus. They belong to the Flaviviridae family, the same as the yellow fever virus. There are four serotypes: DENV-1, DENV-2, DENV-3 and DENV-4, and all can cause both the classic form of the disease and more severe forms.

Although there have been reports of the disease since the mid-1982th century and the beginning of the 1th century in Brazil, the circulation of dengue viruses was only confirmed in the laboratory in 4, when the DENV serotypes were isolated. -1986 and DENV-1, in Boa Vista (RR), leaving the country without notification of cases for four years. In 2, DENV-2001 was isolated in the State of Rio de Janeiro, causing an epidemic and spread of this serotype to different regions of Brazil. Then, with the introduction of DENV-3, also in the State of Rio de Janeiro, the first case of dengue hemorrhagic fever by this serotype was confirmed, with the appearance of severe forms also in other regions. In January 2010, DENV-4 was isolated in the municipality of Nova Iguaú (RJ). In 2011, DENV-4 was isolated from cases detected in the state of Roraima and Amazonas. In January XNUMX, it was isolated in Pará and, in March of the same year, the first cases of DENV-XNUMX in Rio de Janeiro were confirmed by the Instituto Oswaldo Cruz (IOC/Fiocruz).

Monika Barth/IOC

Microscopic image of a mosquito cell infected with the dengue virus (arrows)

transmission and multiplication
The dengue transmission cycle begins when the mosquito Aedes aegypti, vector of the disease in Brazil, bites an infected person. The virus multiplies in the midgut of the vector and infects other tissues, finally reaching the salivary glands. Once infected, the mosquito is capable of transmitting for as long as it lives. There is no transmission of the disease through contact between sick individuals and healthy people. After the mosquito bite, the cycle of viral replication begins in the striated and smooth cells, fibroblasts and local lymph nodes, followed by viremia, with the dissemination of the virus in the organism of the mosquito. individual. The first symptoms such as fever, headache and malaise appear after an incubation period that can vary from 2-10 days. Once infected by one of the virus serotypes, the person acquires immunity to that specific serotype.

Atlas of Dengue Virus Morphology and Morphogenesis
The contents of the Dengue Virus Morphology and Morphogenesis Atlas, which presents the dengue virus and general aspects of infected cells, can be accessed online for free at the IOC. The publication, all in English, describes the morphology of the life cycle of the dengue virus through 115 images accompanied by explanatory texts. The morphogenesis of virus replication is described and discussed by author and head of the Viral Morphology and Morphogenesis Laboratory, Monika Barth. The version available for download has been compressed, so the images are not in printable resolution. Those interested in obtaining copies of the printed version can request by email barth@ioc.fiocruz.br.
Access the full version in PDF

*All contents were reviewed by researchers at Instituto Oswaldo Cruz (IOC/Fiocroz)