Dengue: twenty-five years since reemergence in Brazil.

This article revisits the epidemiology of dengue in Brazil, 25 years after its reemergence in the country, discussing the main determinants and implications for its control. The authors emphasize the clinical and epidemiological peculiarities of this viral disease in Brazil, which leads the world in both the number of cases reported and risk of occurrence of the disease. The article presents the changes occurring in the dengue epidemiological pattern in recent years, like the sudden age shift in the incidence of dengue hemorrhagic fever, and discusses possible associated factors. The article focuses specifically on the epidemic in Rio de Janeiro in 2008, this episode's impact on the international community, and the fear that the disease could spread to Europe. The authors conclude that the current situation emphasizes the need for the international scientific community to renew its efforts to generate knowledge allowing improvement and progress in the development of new tools and strategies for dengue prevention.