Dengue, a reemerging disease, is one of the most important viral diseases transmitted by mosquitoes. Climate is considered an important factor in the temporal and spatial distribution of vector-transmitted diseases. This study examined the effect of seasonal factors and the relationship between climatic variables and dengue risk in the city of Rio de Janeiro, Brazil, from 2001 to 2009. Generalized linear models were used, with Poisson and negative binomial distributions. The best fitted model was the one with "minimum temperature" and "precipitation", both lagged by one month, controlled for "year". In that model, a 1°C increase in a month's minimum temperature led to a 45% increase in dengue cases in the following month, while a 10-millimeter rise in precipitation led to a 6% increase in dengue cases in the following month. Dengue transmission involves many factors: although still not fully understood, climate is a critical factor, since it facilitates analysis of the risk of epidemics.

A febre dengue e suas formas graves (dengue hemorrágica e síndrome do choque da dengue) estão hoje presentes em quase todos os estados do Brasil, com os sorotipos Den-1, Den-2 e Den-3 circulando simultaneamente em 24 estados 10 . A persistência e a progressão desta virose estão condicionadas à sobrevivência e reprodução do seu vetor, a fêmea do mosquito Aedes aegypti, no ambiente. Dado que não existe ainda uma vacina para a dengue, o combate aos criadouros é tido ainda como a melhor estratégia.As ABSTRACTTemperatures in the City of Rio de Janeiro in the first quarter of the year over the period 1986-2003, especially the minimum, were significantly higher in the years in which dengue epidemics started in the city. There was no significant relationship with total rainfall for the same quarter of the year, but epidemics were more frequent in the years in which the volume of rain during the summer was small (less than 200mm).