RESUMO
An urban epidemic of dengue in Senegal during 2009 affected 196 persons and included 5 cases of dengue hemorrhagic fever and 1 fatal case of dengue shock syndrome. Dengue virus serotype 3 was identified from all patients, and Aedes aegypti mosquitoes were identified as the primary vector of the virus.
Assuntos
Vírus da Dengue/classificação , Dengue/epidemiologia , População Urbana , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Dengue/história , Vírus da Dengue/genética , Feminino , História do Século XXI , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Filogenia , Senegal/epidemiologia , Sorotipagem , Dengue Grave/epidemiologia , Dengue Grave/história , Adulto JovemRESUMO
After 8 years of silence, dengue virus serotype 2 (DENV-2) reemerged in southeastern Senegal in 1999. Sixty-four DENV-2 strains were isolated in 1999 and 9 strains in 2000 from mosquitoes captured in the forest gallery and surrounding villages. Isolates were obtained from previously described vectors, Aedes furcifer, Ae. taylori, Ae. luteocephalus, and--for the first time in Senegal--from Ae. aegypti and Ae. vittatus. A retrospective analysis of sylvatic DENV-2 outbreaks in Senegal during the last 28 years of entomologic investigations shows that amplifications are periodic, with intervening, silent intervals of 5-8 years. No correlation was found between sylvatic DENV-2 emergence and rainfall amount. For sylvatic DENV-2 vectors, rainfall seems to particularly affect virus amplification that occurs at the end of the rainy season, from October to November. Data obtained from investigation of preimaginal (i.e., nonadult) mosquitoes suggest a secondary transmission cycle involving mosquitoes other than those identified previously as vectors.