People with a history of severe allergic reactions have a low risk of an adverse event after being vaccinated against COVID-19, a new study shows. File Photo by Gary I Rothstein /UPI | License Photo
Oct. 26 (UPI) -- People with a history of severe allergic reactions to drugs and vaccines can receive both doses of the two-shot COVID-19 inoculations safely, a study published Tuesday by JAMA Network Open found.
Nearly 12% of healthcare workers who reported having a history of allergies to medications, vaccines or allergens such as dust and pollen had an allergic reaction to either the first or second dose of the COVID-19 vaccine, the data showed.
The most common allergic symptoms were hives and angioedema, or swelling, around the injection site, and none of them required hospital treatment, they said.
Despite these symptoms, 98% of the study participants were fully vaccinated against the virus, meaning they received both doses of the two-shot vaccines from Moderna or Pfizer-BioNTech.
"The results of this study can help guide expectations for patients with high-risk allergy histories," study co-author Dr. Lily Li said in a press 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," said Li, a member of the allergy faculty at Brigham and Women's Hospital in Boston.
Earlier studies have indicated that allergic reactions to the two-dose COVID-19 vaccines are rare, even among those with a history of allergies.
Severe allergic reactions such as anaphylaxis, or an extreme immune system response to the vaccines, are also extremely rare, research suggests.
For this study, Li and her colleagues assessed allergy risk among 52,998 healthcare workers in the Brigham and Women's health system, all of whom received at least one dose of a COVID-19 vaccine.
More than 60% of the staff members were given the Moderna vaccine, while the rest received the Pfizer-BioNTech shot, the researchers said.
Among all the study participants, 474, or about 1%, reported a history of severe allergic reactions to medications, vaccines or allergens.
While 12% of those with a history of allergic reactions had one after the vaccine, fewer than 5% of those who did not have a history of allergies had one, the researchers said.
Those with a history of allergic reactions had a 2.5-fold higher risk for allergic reactions to the COVID-19 vaccines, the data showed.
The findings should provide reassurance regarding the safety of mRNA COVID-19 vaccination in individuals regardless of allergy history, the researchers said.
"We hope these data will help inform ongoing conversations with patients who are hesitant to receive COVID-19 vaccination due to allergy concerns," co-author Dr. Kimberly G. Blumenthal said in a press release.
"At our institutions, nearly all individuals with and without a history of high-risk allergy were able to complete the two-dose vaccine series," said Blumenthal, co-director of the Clinical Epidemiology Program at Massachusetts General Hospital in Boston.