Doctor giving Covid vaccine to senior woman

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BOSTON, Mass. — The coronavirus vaccine rollout has had its setbacks over the last year — mostly due to small numbers of patients having allergic reactions. Despite the potential complications, a new study finds COVID-19 vaccines are indeed safe for people with a history of having severe allergic reactions.

The study of health care workers in the United States found that, while those with a history of reactions experienced allergic symptoms after their injections, these side-effects were temporary and nearly every worker was able to receive their second dose.

Researchers from Massachusetts General Hospital discovered that around one in nine workers with a history of allergic reactions (11.6%) had some allergic side-effects after their first dose, compared with 4.7 percent of other workers.

What reactions can the vaccine cause?

Hives and angioedema, a form of swelling on the skin, were the most common reactions. However, almost everyone with (and without) a history of allergies was able to get both doses without adverse side-effects. All study participants at Massachusetts General Brigham hospitals received either the Pfizer or Moderna COVID vaccines.

Both shots use new technology called messenger RNA (mRNA), which uses genetic instructions to teach the body to recognize and fight coronavirus.

“The results of this study can help guide expectations for patients with high-risk allergy histories,” says study lead author Dr. Lily Li in a media release. “Symptoms such as hives and swelling may occur, particularly with the first vaccine dose, but most reported allergic symptoms did not impede completion of the two-dose mRNA vaccine series.”

“We hope these data will help inform ongoing conversations with patients who are hesitant to receive COVID-19 vaccination due to allergy concerns,” adds senior study author Dr. Kimberly Blumenthal. “At our institutions, nearly all individuals with and without a history of high-risk allergy were able to complete the two-dose vaccine series.”

Overall, the study finds that 97.6 percent of the 52,998 health care employees in the study were able to receive both doses of the coronavirus vaccine. Having a history of severe allergic reactions increases the risk of reacting to the COVID vaccine by 2.5 times.

The findings appear in the journal JAMA Open Network.

South West News Service writer Gwyn Wright contributed to this report.

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