While individuals with severe allergies reported more reactions after receiving a COVID-19 mRNA vaccine than those without allergies, nearly all were able to safely complete the series, according to an Oct. 27 study in JAMA Network Open.
Researchers at Boston-based Mass General Brigham and Harvard Medical School used electronic health records of 52,998 employees, of whom 97.6 percent received both doses of vaccine, and 0.9 percent reported a history of high-risk allergy.
Participants completed a pre-vaccination allergy risk assessment and at least one post-vaccination symptom survey three days following vaccination.
Key findings:
- Allergic symptoms emerged more often after the first dose, with most symptoms being mild at 2.7 percent, but respiratory symptoms (1.3 percent), hives (0.9 percent), and angioedema (0.6 percent) were also reported.
- Of the 140 participants who reported severe allergic symptoms after vaccination, 4.3 percent had a history of high-risk allergy.
- The risk of a severe allergic reaction after vaccination was 1.3 percent among workers with a high-risk allergy history and 0.3 percent among those who had never had a high-risk reaction.
- Relative to workers without allergies, those with severe allergies had more reactions after receiving one or two vaccine doses (11.6 percent vs 4.7 percent). Risks were highest for hives and angioedema.
"However, reported allergy symptoms did not impede the completion of the 2-dose vaccine protocol among a cohort of eligible health care employees, supporting the overall safety of mRNA COVID-19 vaccine," researchers concluded.
Read the full study here.