Relationship between pre-existing allergies and anaphylactic reactions post mRNA COVID-19 vaccine administration

Two mRNA vaccines for COVID-19, Pfizer-BioNTech and Moderna, are approved for emergency use in the United States. After their approval and dosing in millions of recipients, reports of anaphylaxis began to appear in the Vaccine Adverse Reporting System (VAERS). Here we provide an analysis of the relationship between prior history of allergy and/or anaphylaxis and anaphylaxis rates following the administration of mRNA COVID-19 vaccines. Overall reported incidence of anaphylaxis was estimated to be rare at 4.2 cases per million doses. It appeared that the relative incidence of anaphylaxis following administration of these COVID-19 vaccines was two and seven times higher for recipients with a prior history of allergies and/or anaphylaxis, respectively. This report provides valuable metrics to make evidence-based decisions for subjects with pre-existing allergic conditions receiving a COVID-19 mRNA vaccine. (c) 2021 Published by Elsevier Ltd.

Automated summary

The Pfizer-BioNTech and Moderna mRNA vaccines for COVID-19 are approved for emergency use in the US, with a rare reported incidence of anaphylaxis. Recipients with prior history of allergies and/or anaphylaxis have higher relative incidence of anaphylaxis following vaccination, providing valuable metrics for evidence-based decisions.