Is the incidence of anaphylaxis from COVID-19 vaccines higher than initially thought?

Thursday, September 9, 2021
By Austin Tannenbaum

While one study of limited scope found an unusually high incidence of anaphylaxis in COVID-19 vaccine recipients, the authoritative source on adverse vaccination events found an incidence in line with the Centers for Disease Control’s figure of “approximately 2 to 5 people per million” for life-threatening allergic reactions.

The outlier study was limited to fewer than 65,000 employees at a Massachusetts hospital. Sixteen experienced anaphylaxis — a rate of two per ten thousand. Two-thirds of those who did “had an allergy history”—a known risk multiplier.

In a much broader study, the Vaccine Adverse Event Reporting System, a government vaccine safety mechanism that requires health care professionals to report adverse effects, documented 66 anaphylaxis cases out of more than 17.5 million vaccine doses—a rate of approximately four per million.

Providers monitor recipients following vaccination. Epinephrine, the first-line treatment for anaphylaxis, is kept on hand.

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