Serious adverse events rarely reported after trivalent inactivated influenza vaccine (TIV) in children 6–23 months of age

In October 2003 the Advisory Committee on Immunization Practices (ACIP) recommended influenza vaccination for all children ages 6–23 months. We evaluated the safety of this recommendation by querying the Vaccine Adverse Events Reporting System (VAERS) for serious adverse events (SAE) reported between July 1, 2003 and June 30, 2006 in 6–23 month old infants after trivalent inactivated influenza vaccine (TIV). Cases were reviewed and the causal relationship with vaccine assessed. One hundred and four SAE were reported; median time from vaccination to SAE onset was one day. The two most commonly reported SAE disease categories were fever (N = 52) and seizure (N = 35). Causality assessment revealed that none of the SAE was definitely related to TIV. Although the number of SAE increased over time, the most common types of events remained unchanged with no new or unexpected safety concerns identified with expanded TIV use.