Key Points
ÎImmunization is perhaps the greatest public health achievement of all time, having significantly reduced the morbidity and mortality of many infectious diseases.
ÎThere are approximately 235 million doses of vaccines administered in the United States each year.
ÎAnaphylactic reactions to vaccines are estimated to occur at a rate of approximately 1 per million doses.
ÎPatients with suspected allergy to vaccines or vaccine components should be evaluated by an allergist/immunologist.
ÎMost patients with suspected allergy to vaccines can receive vaccination safely.
Diagnosis and Assessment
ÎMild local reactions and constitutional symptoms, such as fever, after vaccinations are common and do not contraindicate future doses. Rarely, delayed-type hypersensitivity to a vaccine constituent may cause an injection site nodule, but this is not a contraindication to subsequent vaccination. (C)
ÎAll serious events occurring after vaccine administration should be reported to the Vaccine Adverse Event Reporting System (http://vaers.hhs.gov/), even if it is not certain that the vaccine was causal. (C)
ÎMeasuring levels of IgG antibody to the immunizing agent in a vaccine suspected of causing a serious adverse reaction to determine if they are at protective levels can help determine whether or not subsequent doses are required. (B)
ÎAll suspected anaphylactic reactions to vaccines should ideally be evaluated in an attempt to determine the culprit allergen. (B)
ÎIgE-mediated reactions to vaccines are more often caused by vaccine components, such as gelatin or egg protein, than the immunizing agent itself. (B)
ÎPatients who have had an apparent anaphylactic reaction after immunization should undergo immediate-type allergy skin testing to help confirm that the reaction was IgE-mediated and to determine the responsible component of the vaccine. (B)
