Allergic Reactions to the Pfizer-BioNTech and Moderna COVID-19 Vaccines: Early Reports

The CDC's reports in late December 2020 and January 2021 indicated rates of 11.1 and 2.5 anaphylaxis cases per million vaccine doses of the Pfizer-BioNTech and Moderna vaccines, respectively, with no fatalities.

An initial CDC report detailed adverse reactions (including anaphylaxis) during the first 10 days of administration of the Pfizer-BioNTech COVID-19 vaccine. During that period (December 14–23, 2020), 1,893,360 first doses of vaccine (encompassing multiple lots) were given and 4393 adverse reactions (0.2%) were reported. Twenty-one of these cases were subsequently defined as anaphylaxis (median age, 40; 90% women), for an incidence of 11.1 per million vaccinations. Median onset of anaphylaxis was 13 minutes (range, 2–150 minutes), with 71% of reactions occurring within 15 minutes (the recommended observation period), 14% within 15–30 minutes, and an additional 14% after 30 minutes. Epinephrine (primarily intramuscular) was administered and n…

Reviewing Author

Stephen G. Baum, MD

Disclosures

Consultant/Advisory BoardClinical Infectious Diseases

RoyaltiesUpToDate

Editorial BoardsMedical Letter

Stephen G. Baum, MD

Disclosures

Consultant/Advisory BoardClinical Infectious Diseases

RoyaltiesUpToDate

Editorial BoardsMedical Letter

Allergic Reactions to the Pfizer-BioNTech and Moderna COVID-19 Vaccines: Early Reports

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Reviewing Author