Emerging and reemerging diseases in Brazil: data of a recent history of risks and uncertainties.

This article discusses the emergence and reemergence of infectious diseases on the basis of a review of the literature. It shows the critical situations faced worldwide and in special Brazil's susceptible position due to its complexity, mostly represented by the mega-biodiversity of the country and its socio-economic problems directly affecting public health. It approaches the discussions around the issue with emphasis to the recommended investments in the health sector, directed to surveillance and to strengthening the epidemiological, laboratorial and clinical bases and centered on preventive and control measures in the affected areas including Biosafety.