Influenza virus vaccine(ID Biomedical Corporation)

Many Canadians received a novel AS03-adjuvanted vaccine during the 2009 influenza A/H1N1 pandemic. Longer term implications of adjuvant use were unclear: would anti-H1N1 immune responses persist at high levels and, if so, could that result in increased or unusual adverse effects upon re-exposure to H1N1pdm09 antigen in the trivalent influenza vaccine (TIV) for 2010-11? To answer these questions, adults given AS03-adjuvanted H1N1pdm09 vaccine (Arepanrix®, GSK Canada) 9-10 mo earlier were enrolled in an evaluator-blinded, crossover trial to receive 2010-2011 non-adjuvanted TIV (Fluviral®, GSK Canada) and placebo 10 d apart, in random order. Adverse effects were monitored for 7 d after each injection. Vaccine-attributable adverse event (VAAE) rates were calculated by subtracting rates after placebo from those after vaccine. Blood was obtained pre-vaccination and 21-30 d afterward to measure hemagglutination inhibiting antibody titers. In total, 326 participants were enrolled and 321 completed the study. VAAE rates were low except for myalgia (18.6%) and injection site pain (63.2%). At baseline, H1N1pdm09 titers ≥ 40 were present in 176/325 subjects (54.2%, 95% confidence interval 48.6, 59.7), with a geometric mean titer (GMT) of 37.4 (95% CI 32.8, 42.6). Post-immunization, 96.0% (95% CI 92.3, 97.8) had H1N1pdm09 titers ≥ 40, with GMT of 167.4 (95% CI 148.7, 188.5). Responses to both influenza A strains in TIV were similar, implying no lasting effect of adjuvant exposure. In summary, titers ≥ 40 persisted in only half the participants 9-10 mo after adjuvanted pandemic vaccine but were restored in nearly all after TIV vaccination, with minimal increase in adverse effects.

Oculo-respiratory syndrome (ORS) following influenza vaccination was identified in Canada in 2000. This report describes trends of ORS reported during four consecutive seasons 2000, 2001, 2002 and 2003 in the province of Quebec, Canada.

Data come from the vaccine-associated adverse event (VAAE) passive reporting system of the Province of Quebec.

The rate of ORS reported per 100000 doses distributed declined from 46.6 in 2000 to 34.2, 20.6 and 9 in 2001, 2002 and 2003, respectively. There was no significant difference in rates for ORS between the two vaccines in use in Canada (Fluviral and Vaxigrip) both in 2001 and 2002. During the 4 years, incidence was highest in people aged 40-59 years and declined in older age groups. The clinical profile of ORS has remained remarkably stable over years. Overall, ocular, respiratory symptoms or facial edema were reported by 58%, 84% and 31% of patients, respectively, and 15% had symptoms including all three symptom categories. ORS lasted more than a week in 8-13% of the cases.

ORS is an adverse event that occurred with both influenza vaccines used in Canada. Its frequency has declined substantially but is still present after 4 years. It constitutes a clinical entity distinct from anaphylactic allergy. Unlike anaphylaxis, ORS does not constitute an absolute contraindication to further doses.