Frequency of medically attended events following rapid revaccination with trivalent inactivated influenza vaccine.

In 2008, potential temperature compromise of one lot of trivalent inactivated influenza vaccine (TIV) led to the revaccination of 13,210 Kaiser Permanente Northwest members within 28 days of receipt of their initial TIV dose. We conducted a retrospective cohort study to determine if these individuals experienced a higher rate of medically attended events (MAE) than those receiving only one TIV dose. We found no increase in MAE among those rapidly revaccinated (odds ratio 1.08; 95% confidence interval 0.80, 1.45), which may reassure individuals of the safety of revaccination with TIV should it be necessary, thereby leading to increased compliance with influenza vaccination recommendations.