Frequency of medically attended adverse events following tetanus and diphtheria toxoid vaccine in adolescents and young adults: a Vaccine Safety Datalink study.
BACKGROUND
Local reactions are the most commonly reported adverse events following tetanus and diphtheria toxoid (Td) vaccine and the risk of local reactions may increase with number of prior Td vaccinations.


METHODS
To estimate the risk of medically attended local reactions following Td vaccination in adolescents and young adults we conducted a six-year retrospective cohort study assessing 436,828 Td vaccinations given to persons 9 through 25 years of age in the Vaccine Safety Datalink population from 1999 through 2004.


RESULTS
Overall, the estimated risk of a medically attended local reaction was 3.6 events per 10,000 Td vaccinations. The lowest risk (2.8 events per 10,000 vaccinations) was found in the 11 to 15 year old age group. In comparison with that group, the event risks were significantly higher in both the 9 to 10 and 21 to 25 year old age groups. The risk of a local reaction was significantly higher in persons who had received another tetanus and diphtheria toxoid containing vaccine (TDCV) in the previous five years (incidence rate ratio, 2.9; 95% confidence interval, 1.2 to 7.2). Twenty-eight percent of persons with a local reaction to Td vaccine were prescribed antibiotics.


CONCLUSIONS
Medically attended local reactions were uncommon following Td vaccination. The risk of those reactions varied by age and by prior receipt of TDCVs. These findings provide a point of reference for future evaluations of the safety profile of newer vaccines containing tetanus or diphtheria toxoid.
Group Health Research Institute, Seattle WA, USA. jackson.l@ghc.org
Lisa A
LA
Jackson
Onchee
O
Yu
Edward A
EA
Belongia
Simon J
SJ
Hambidge
Jennifer
J
Nelson
Roger
R
Baxter
Allison
A
Naleway
Charlene
C
Gay
James
J
Nordin
James
J
Baggs
John
J
Iskander
D000293:Adolescent; D000328:Adult; D002648:Child; D015331:Cohort Studies; D022422:Diphtheria-Tetanus Vaccine / Q000009:adverse effects*; D006801:Humans; D012189:Retrospective Studies; D012307:Risk Factors; D014611:Vaccination / Q000009:adverse effects*; D055815:Young Adult
D022422:Diphtheria-Tetanus Vaccine