Whereas healthcare staff at a Boston healthcare system with extreme allergy symptoms reported extra reactions after receiving a COVID-19 mRNA vaccine, almost all had been capable of safely full the collection, in line with an observational examine yesterday in JAMA Community Open.
Researchers at Mass Basic Brigham and Harvard Medical College mined the digital well being data of 52,998 staff, of whom 97.6% obtained each doses of vaccine, and 0.9% reported a historical past of high-risk allergy. The examine interval was Dec 14, 2020, to Feb 1, 2021. Contributors accomplished a prevaccination allergy danger evaluation and at the very least one postvaccination symptom survey through the 3 days after vaccination.
Present contraindications to COVID-19 mRNA vaccination embrace a historical past of extreme or rapid allergic reactions to any vaccine part or to a earlier dose of an mRNA vaccine. The staff, nevertheless, got the vaccine in line with Facilities for Illness Management and Prevention pointers, allergist session, danger stratification, and shared decision-making.
Price of extreme reactions: 0.3%
Allergic signs emerged extra typically after the primary reasonably than the second dose. Most signs had been delicate (eg, rash, itching), at 2.7%, however respiratory signs (1.3%), hives (0.9%), and angioedema (swelling of the face, lips, eyes, or tongue) (0.6%) had been additionally reported.
Extreme allergic reactions had been uncommon (0.3%). Of the 140 contributors who reported extreme allergic signs after vaccination, 4.3% had a historical past of high-risk allergy. The danger of a extreme allergic response after vaccination was 1.3% amongst staff with a high-risk allergy historical past and 0.3% amongst those that had by no means had a high-risk response.
Relative to staff with out allergy symptoms, these with extreme allergy symptoms had extra reactions after receiving one or two vaccine doses (11.6% vs 4.7%). After adjustment, high-risk allergy was tied to elevated danger of reactions (adjusted relative danger [aRR], 2.46; 95% confidence interval [CI], 1.92 to three.16). Dangers had been highest for hives (aRR, 3.81; 95% CI, 2.33 to six.22) and angioedema (aRR, 4.36; 95% CI, 2.52 to 7.54).
“Nonetheless, reported allergy signs didn’t impede the completion of the 2-dose vaccine protocol amongst a cohort of eligible well being care staff, supporting the general security of mRNA COVID-19 vaccine,” the examine authors wrote.
Contributors had been, on common, 42 years previous, and 72% had been girls. Girls and Black contributors made up a lot larger proportions of these with a historical past of extreme allergy than these with no historical past of allergy (80.8% vs 71.9% and 9.5% vs 4.8%, respectively).
Severely allergic vaccinees had been older than these with no allergy historical past (46 vs 42 years on common), had extra atopic (allergic) pores and skin circumstances (16.7% vs 8.7%), anxiousness (28.9% vs 23.9%), hypertension (14.6% vs 10.9%), and cancerous tumors (4.0% vs 2.4%).
Contributors at highest danger of allergic reactions to the vaccine had been Black (RR, 1.69), had the next Charlson comorbidity index rating (RR, 1.04), and obtained the Moderna reasonably than the Pfizer vaccine (RR, 1.49). In contrast with girls, males had been at decreased danger for a response (RR, 0.66).
Amongst 474 staff with a historical past of extreme allergy, 46.6% had a earlier response to an unknown or identified allergen (eg, meals, venom, drug, latex). Almost 46% of those staff reported a earlier extreme allergic response to an injectable medicine or vaccine. Only one.9% had a earlier extreme allergic response to polyethylene glycol (PEG) (an inert vaccine ingredient) or PEG-containing merchandise (eg, Miralax, injectable steroid).
Folks with historical past of reactions ought to seek the advice of allergist
Quickly after the US Meals and Drug Affiliation issued an emergency use authorization for the mRNA COVID-19 vaccines from Pfizer/BioNTech and Moderna in December 2020, a number of extreme allergic reactions had been reported, elevating considerations about vaccine security, the researchers famous.
Since then, the reported price of allergic reactions to those vaccines has been about 2%, and anaphylaxis (a extreme, probably life-threatening allergic response) has been estimated to happen in 0.025 to 2.47 instances per 10,000 vaccinations—or a 0.02% danger on the excessive finish of that vary. Of vaccinees who skilled anaphylaxis after vaccination, a couple of third had a historical past of the response.
Whether or not extreme allergy symptoms are linked to allergic reactions after mRNA vaccination remains to be unclear, the authors famous, as a result of the noticed reactions might not be true allergy symptoms. Folks with a historical past of extreme allergy to PEG ought to seek the advice of their allergist or immunologist earlier than in search of COVID-19 vaccination; such an allergy might not be a contraindication for vaccination.
“Identification of danger components for allergy signs after COVID-19 vaccination will information secure vaccination practices for people on the highest danger and inform methods that concentrate on vaccine hesitancy that’s related to allergy considerations,” the researchers wrote.
Total, the outcomes are reassuring for individuals who have a historical past of extreme allergy, senior creator Kimberly Blumenthal, MD, stated in a Massachusetts Basic Hospital information launch.
“We hope these information will assist inform ongoing conversations with sufferers who’re hesitant to obtain COVID-19 vaccination on account of allergy considerations,” she stated. “At our establishments, almost all people with and with no historical past of high-risk allergy had been capable of full the two-dose vaccine collection.”