Annual report: surveillance of adverse events following immunisation in Australia, 2009.

This report summarises Australian passive surveillance data for adverse events following immunisation (AEFI) reported to the Therapeutic Goods Administration (TGA) for 2009, and describes reporting trends over the 10-year period 2000 to 2009. There were 2,396 AEFI records for vaccines administered in 2009, the highest number reported, a 46% increase over the 1,638 in 2008. The increase was almost entirely due to reports related to the introduction of pandemic H1N1 (pH1N1) 2009 influenza vaccine from September 2009 (n = 1,312) largely from the members of the public. The pH1N1 AEFI reporting rate for people aged > or = 18 years was 34.2 per 100,000 administered doses compared with 2.8 for seasonal influenza vaccine. The rates in > or = 65 year-olds were 28.0, 1.6 and 13.3 for pH1N1, seasonal influenza and polysaccharide pneumococcal, respectively. The high reporting rate for pH1N1 vaccine is likely to be at least partly due to enhanced reporting seen for all new vaccines and greater levels of reporting from members of the public in response to the implementation of strategies to encourage reporting, as part of the pH1N1 program. For children < 7 years, AEFI reporting rates in 2009 (14.1 per 100,000 administered doses) were similar to previous years. There were 193 (8%) AEFI reports classified as serious; 6 deaths temporally associated with immunisation were reported but none were judged to have a causal association. As in previous years, the most commonly reported reactions were allergic reaction, injection site reaction, fever, headache, malaise, nausea and myalgia. The most commonly reported reactions following pH1N1 influenza vaccine were allergic reaction (n = 381), headache (n = 289), fever (n = 235), pain (n = 186), nausea (n = 180) and injection site reaction (n = 178). The data within the limitation of passive surveillance provide a reference point for ongoing reporting of trends in AEFI by age group, severity and vaccine type and illustrate the value of the national TGA database as a surveillance tool for monitoring AEFI nationally.