Anaphylaxis following administration of the Pfizer-BioNTech coronavirus disease 2019 (COVID-19) vaccine occurred at a rate of 11.1 per 1 million doses, according to a clinical update published in JAMA.
The authors retrospectively reviewed the Vaccine Adverse Event Reporting System (VAERS) for reports of suspected severe allergic reaction and anaphylaxis following administration of the Pfizer-BioNTech COVID-19 vaccine.
A total of 1,893,260 doses of the Pfizer-BioNTech COVID-19 vaccine were administered between December 14 and 23, 2020; of which 1,117,577 were administered to women, 648,327 administered to men, and 67,506 were unreported. A total of 21 cases were reported to the VAERS that met the definition for anaphylaxis, which is a rate of 11.1 per 1 million doses. Additionally, 17of the 21 patients with anaphylaxis, had a medical history of allergy or allergic reactions, and 7 had experienced anaphylaxis in the past. The average time to symptom onset was 13 minutes. No deaths were reported.
“Widespread vaccination against COVID-19 with highly effective vaccines represents an important tool in efforts to control the pandemic,” the study authors wrote. “Patients experiencing anaphylaxis should be transported to facilities to receive appropriate medical care.”
Shimabukuro T, Nair N. Allergic reactions including anaphylaxis after receipt of the first dose of Pfizer-BioNTech COVID-19 vaccine. JAMA. Published online January 21, 2021. doi:10.1001/jama.2021.0600