RESUMO
Severe forms of dengue fever, dengue haemorrhagic fever, and dengue shock syndrome, were not prominent in the Americas until the epidemic of Cuba in 1981. Since that time, they have spread to other countries in Central and South America, correlating with the spread of dengue type 2 viruses related to Southeast Asian strains. We report here the complete genomic sequence of a dengue type 2 virus isolated during the epidemic in La Martinique in 1998. This constitutes the first complete genetic characterization of a dengue virus strain from French West Indies, and also the first molecular identification in this region of a dengue 2 strain phylogenetically related to the emerging American type 2 dengue viruses.
Assuntos
Vírus da Dengue/genética , Dengue/virologia , Genoma Viral , Substituição de Aminoácidos/genética , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Dengue/epidemiologia , Vírus da Dengue/química , Vírus da Dengue/classificação , Humanos , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência , Sorotipagem , Índias Ocidentais/epidemiologiaRESUMO
Yellow fever was presumably imported to the Americas from West-Africa from the 16th to the 19th century. American and African genotypes of the virus are distinguishable, indicating separate evolution in different vector/host cycles. The complete nucleotide sequence of the yellow fever virus strain TRINID79A, isolated in Trinidad in 1979, has been established. It exhibits extensive homology with those of current West-African strains and attenuated strain FNV. However, a unique deletion of the 3' non-coding region (NCR) of the viral RNA has been identified. It indicates that RYF1 and RYF2 repeated sequences of the 3' NCR are not necessary to the replication of the virus.
Assuntos
Genoma Viral , Filogenia , Vírus da Febre Amarela/genética , Regiões 3' não Traduzidas/genética , Sequência de Bases , DNA Complementar , Dados de Sequência Molecular , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Trinidad e Tobago , Vírus da Febre Amarela/classificaçãoRESUMO
Dengue has become a major public health problem in intertropical areas where an estimated 60 million new cases and 30,000 deaths occur annually. The causative agent is transmitted by the bite of Aedes mosquitoes which are the main and perhaps only reservoir of the disease. In addition to increasing incidence clinical manifestations of dengue have changed over the last 40 years. An increasing number of reported cases involve hemorrhage, shock, and other severe complications especially in Southeast Asia, northern regions of South America, and the Caribbean. Some of the same factors responsible for these changes are probably implicated in the development of other emerging viral diseases.