[Analysis of the Vaccine Adverse Event Reporting System in Brazil, 2014 to 2016Análisis del Sistema de Información de Vigilancia de Eventos Adversos Posvacunación en Brasil, 2014 a 2016].

Objective. To describe the characteristics of vaccine adverse events (VAE) reports in the online VAE Reporting System (VAE-RS) after 2 years of operation. Method. A descriptive analysis of VAE reports entered into the VAE-RS between July 2014 and June 2016 was performed. Results. During the study period, 24 732 VAE were reported. Of 5 570 Brazilian municipalities, 2 571 (462%) reported at least one VAE; however, only 1 622 (6.6%) reports had been completed/closed at the end of the study period. Of these, 89.9% referred to mild VAE. Among the completed reports, 19.7% did not provide information on "type of medical care provided," and 98.7% had no information regarding laboratory tests. Systemic neurological symptoms were the most frequent serious VAE among closed reports (59.5% of serious signs/symptoms). Concerning age, the highest VAE reporting coefficients were recorded for children aged <= 4 years. Conclusion. The VAE-RS is useful to monitor immunization safety. However, municipal services must increase adherence to the system and perform the required investigation and reporting of VAE, with timely and adequate completion of the VAE-RS form. Knowledge regarding VAE can be used in the daily routine of surveillance services, improving the safety of immunobiological agents.