Epidemiologic surveillance of dengue fever in Mexico.

The clinical behavior of dengue fever in Mexico has changed now with the occurrence of hemorrhagic cases. In response to the emergence of such cases, a specific epidemiologic surveillance system has been designed and implemented. This system includes the means to monitor the factors involved in the evolution of the disease. The identification and analysis of these factors is necessary to implement prevention and control measures. This paper presents the main components and procedures of the epidemiologic surveillance system for common and hemorrhagic dengue fever in Mexico, emphasizing the usefulness of the risk approach to predict the pattern of this disease. The model includes the collaboration of a multidisciplinary group. The Epidemiologic Surveillance State Committee, coordinated by the National Health System, participates in the collection and analysis of epidemiologic data, particularly data related to the population, the individual, the vector, the viruses and the environment.