title: Reduced reaction frequencies with repeated inactivated or live-attenuated influenza vaccination.
abstract: Data collected as part of a multi-year trial examining the efficacies of inactivated and live-attenuated influenza vaccines were used to evaluate the reported occurrence of post-vaccination reactions. Two cohorts were defined: (1) individuals who received the same vaccine over two consecutive years, and (2) individuals who first enrolled in year 2 of the study and received vaccine only in that year. For both vaccines there were significantly fewer reactions reported in year 2 in those subjects who were vaccinated both years. Declines were demonstrated when comparing year 1 and 2 reaction frequencies in subjects vaccinated both years, and differences were seen when comparing year 2 reaction frequencies in subjects vaccinated both years with those first vaccinated in year 2. Reaction reporting peaked on post-vaccination days 0 and 1 following receipt of the inactivated vaccine, and on day 2 following receipt of the live-attenuated vaccine.
authors.affiliation: University of Michigan School of Public Health, Ann Arbor, MI 48109, USA.
authors.forename: Suzanne E
authors.initials: SE
authors.lastname: Ohmit
authors.forename: Jonathan
authors.initials: J
authors.lastname: Gross
authors.forename: John C
authors.initials: JC
authors.lastname: Victor
authors.forename: Arnold S
authors.initials: AS
authors.lastname: Monto
mesh_terms: D000293:Adolescent; D000328:Adult; D015331:Cohort Studies; D064420:Drug-Related Side Effects and Adverse Reactions / Q000453:epidemiology*; D005260:Female; D006801:Humans; D015994:Incidence; D007252:Influenza Vaccines / Q000009:adverse effects* / Q000276:immunology; D007251:Influenza, Human; D008297:Male; D008875:Middle Aged; D010919:Placebos / Q000008:administration & dosage; D013997:Time Factors; D014611:Vaccination / Q000379:methods*; D014613:Vaccines, Attenuated / Q000009:adverse effects / Q000276:immunology; D015164:Vaccines, Inactivated / Q000008:administration & dosage / Q000009:adverse effects; D055815:Young Adult
chemical_list: D007252:Influenza Vaccines; D010919:Placebos; D014613:Vaccines, Attenuated; D015164:Vaccines, Inactivated