Enhanced surveillance for adverse events following immunization: Two years of dTap catch-up among high school students in Yukon, Canada (2004, 2005).
BACKGROUND
To address the increasing age of pertussis cases, Yukon replaced the Grade 9 tetanus/diphtheria/inactivated polio booster with diphtheria/tetanus/acellular pertussis (dTap) and implemented a dTap catch-up program for Grade 12 students. The program began in June 2004, making Yukon one of the first Canadian jurisdictions to introduce dTap within five years of a tetanus booster. We implemented enhanced surveillance to monitor adverse events following immunization (AEFI) to determine whether students receiving dTap > or =3 to <5 years after their last tetanus booster were at increased risk of severe AEFI.


METHODS
Students completed a self-administered AEFI questionnaire one week post-dTap vaccination. Public health professionals contacted students reporting severe AEFI. Health care providers were requested to report AEFI. Symptom rate, severity and duration were compared between students receiving dTap > or =3 to <5 years after their last tetanus booster and those receiving it >5 years later.


RESULTS
The > or =3 to <5 years group was more likely than the > or =5 years group to report pain at the injection site (70.6% vs. 61.5%, p=0.038) and less likely to report injection site redness (10.0% vs. 17.3%, p=0.022), injection site swelling (8.9% vs. 16.4%, p=0.013), decreased energy (10.0% vs. 17.1%, p=0.023), body aches (2.2% vs. 7.2%, p=0.014) and sore joints (3.3% vs. 10.1%, p=0.004). Severe AEFI did not differ between the groups (3.3% vs. 5.6%, p=0.232). Health care professionals reported no AEFI.


CONCLUSIONS
Results suggest no increased risk of severe AEFI among students receiving dTap > or =3 to <5 years after their last tetanus booster.
David
Samara T
ST
Canadian Field Epidemiology Program, Public Health Agency of Canada, Ottawa, ON. samara.david@bccdc.ca
Hemsley
Mhsc Colleen
MC
Pasquali
Paula E
PE
Larke
Bryce
B
Buxton
Jane A
JA
Lior
Lee Y
LY
D000293:Adolescent; D016907:Adverse Drug Reaction Reporting Systems; D017677:Age Distribution; D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines / Q000008:administration & dosage / Q000009:adverse effects*; D005221:Fatigue / Q000139:chemically induced; D006801:Humans; D017589:Immunization Programs / Q000592:standards; D007115:Immunization Schedule; D007117:Immunization, Secondary / Q000009:adverse effects* / Q000592:standards; D007271:Injections, Intradermal / Q000009:adverse effects; D007596:Joints / Q000187:drug effects; D010146:Pain / Q000209:etiology; D011159:Population Surveillance; D018570:Risk Assessment; D013745:Tetanus Toxoid / Q000008:administration & dosage / Q000009:adverse effects; D014917:Whooping Cough / Q000453:epidemiology / Q000517:prevention & control*; D015874:Yukon Territory / Q000453:epidemiology
D022681:Diphtheria-Tetanus-acellular Pertussis Vaccines; D013745:Tetanus Toxoid