Post-Licensure Surveillance of Trivalent Live-Attenuated Influenza Vaccine in Children Aged 2-18 Years, Vaccine Adverse Event Reporting System, United States, July 2005-June 2012

Background. The first trivalent live-attenuated influenza vaccine (LAIV3) was licensed in 2003 for use in healthy persons 5-49 years of age. In 2007, the US Food and Drug Administration expanded its indication to healthy children 2-4 years of age. Methods. We searched the Vaccine Adverse Event Reporting System (VAERS) for US reports after LAIV3 from July 1, 2005 to June 30, 2012 in children aged 2-18 years. Medical records were requested for nonmanufacturer reports coded as serious (ie, death, hospitalization, prolonged hospitalization, life-threatening illness, disability). We characterized electronic data and clinically reviewed all serious reports and reports of special interest. Empirical Bayesian data mining was used to identify new or unexpected adverse events (AEs). Results. During the study period, VAERS received 2619 US LAIV3 reports for children aged 2-18 years; 197 (7.5%) reports were serious, including 5 deaths. The 2 most frequent nonfatal serious reports involved neurological and respiratory systems, with 56 (29.2%) and 43 (22.4%) reports, respectively. The most frequent neurological diagnoses were seizures and Guillain-Barre Syndrome, and the most frequent respiratory conditions were pneumonia and asthma or reactive airway disease. Data mining showed increased proportions for reports of medication errors, most commonly vaccine administration errors not associated with an AE. Conclusions. In this VAERS analysis of reports following LAIV3, we found no new or unexpected AEs patterns. Reports of LAIV3 administration to persons, for whom it is not recommended, including children with a history of asthma or reactive airway disease or wheezing, indicate that ongoing monitoring and education in vaccine indications are needed.