Solicited adverse events after influenza immunization among infants, toddlers, and their household contacts.
OBJECTIVE
We assessed adverse events, including oculorespiratory syndrome, following influenza immunization during the first year of a publicly-funded program for infants, toddlers and their household members in Canada.


METHODS
Parents bringing infants and toddlers for influenza immunization to clinics in Quebec or British Columbia consented to structured telephone interview 5 to 10 days later. One adult provided information for all household members. Symptom experience commencing before and after immunization was assessed. Non-immunized persons also served as a comparison group for immunized household members.


RESULTS
Sample included 690 immunized infants and toddlers and 1801 household members, 1374 immunized. Only fussiness, fever, decreased appetite, drowsiness, and nasal congestion/coryza were reported for >5% of infants/ toddlers within 72 hours of immunization, but only arm discomfort was reported among >5% of immunized household contacts. In multivariate analysis, muscle ache was the only systemic symptom reported more often by immunized household members compared to non-immunized persons. Oculorespiratory symptoms were infrequent and there was no difference between immunized and non-immunized household members in their report. Less than 1% of adults required time off work because of adverse events following influenza immunization in the household. Less than 2% of subjects experiencing an adverse event following influenza immunization were considered unlikely to be vaccinated again.


CONCLUSIONS
Influenza vaccine is well-tolerated by infants, toddlers and their household members. Post-marketing observational designs are an expedient way to assess adverse events following influenza immunization. These methods should be established and rehearsed annually in preparation for a pandemic.
Skowronski
Danuta M
DM
British Columbia Centre for Disease Control, Vancouver, British Columbia, Canada. danuta.skowronski@bccdc.ca
Jacobsen
Karen
K
Daigneault
Jocelyne
J
Remple
Valencia P
VP
Gagnon
Linda
L
Daly
Patricia
P
Arsenault
Gillian
G
Landry
Monique
M
Pielak
Karen
K
Duval
Bernard
B
Tam
Theresa
T
De Serres
Gaston
G
D002675:Child, Preschool; D005192:Family Health; D005260:Female; D006801:Humans; D007223:Infant; D007252:Influenza Vaccines / Q000009:adverse effects*; D008297:Male; D015999:Multivariate Analysis; D015164:Vaccines, Inactivated / Q000009:adverse effects*
D007252:Influenza Vaccines; D015164:Vaccines, Inactivated; C478242:vaxigrip