Assessment of sex-specific differences in adverse events following immunization reporting in Ontario, 2012–15

Abstract We assessed sex-specific trends within passive vaccine safety surveillance in Ontario, Canada. AEFIs reported following vaccines administered between 2012 and 2015 were included. There were 2466 AEFI reports; 66.2% were female. Annualized reporting rates were 5.9 and 3.1 per 100,000 population, for females and males respectively. The female:male reporting rate ratio (RRR) was 1.9. Sex-specific differences by age group were greatest in adults 18–64 years (RRR 6.3); whereas there were no differences in children