[Endemic dengue: surveillance strategy challenges].

Interaction between clinical infection, vector, and population serotype immunity defines dengue epidemic risk. An endemic-sporadic epidemiological situation is an acceptable control target in metropolitan regions deficient in urban upgrading, sanitation, and health agents' access to residences, besides low residual power of biological insecticides and social mobilization problems. Surveillance requires continued action by government and society (particularly when incidence decreases) and adequate proposals. To establish a sensitive and specific surveillance system for endemic periods, the authors propose the sentinel clinical component as part of emergency care (detecting serious tip-of-the-iceberg cases) and reference services for acute febrile diseases, defining clinical forms and providing diagnostic confirmation. Although complex, sample serotype surveys should be conducted in strategic areas, evaluating: immunity and susceptibility of age groups to circulating serotypes; estimation of sub-clinical cases; and Surveillance and Control System reach.