ACAAI is reviewing guidelines for allergic reactions following COVID-19 vaccines

The American College of Allergy, Asthma and Immunology (ACAAI) has updated its guidance on the risk of allergic reactions following the administration of the COVID-19 vaccine now includes information on screening, observation times, and the option to carry forward the second dose after a scheduled document. allergic reactions from the first dose.

The ACAAI COVID-19 Vaccine Action Group has monitored real-time data from sources reporting allergic reactions following the COVID-19 vaccine to the latest recommendations from the U.S. Centers for Disease Control and Prevention (CDC) ) and the U.S. Food and Drug Administration. (FDA).

New Guidance

The new guidelines require patients to be screened for the potential risk of an allergic reaction to any of the 3 vaccines and to be referred to a certified allergist or immunologist. boards for further assessment if the person has a history of severe allergic reactions.

According to CDC guidelines, anyone who has had an adverse reaction should not immediately experience an allergic reaction within 4 hours of receiving the first dose of COVID-19.

In addition, patients who have suffered a severe or immediate sensory reaction should have no anxiety, including kidney, swelling, or wheezing, or who have issues related to the risk of recurrence. -sensitive awareness go to a local board certified allergist / immunologist to provide more care or advice.

In general, the vaccines should be given in a health care setting where anaphylaxis could be treated and all recipients should watch for 15-30 minutes after injection. Most reported cases of anaphylaxis have occurred within 15 minutes of administration.

Finally, the mRNA or adenovirus vector vaccines should not be given to people with a known history of severe allergic reactions to any part of a particular vaccine.

Allergic reactions

Although the specific component that causes anaphylaxis has not yet been identified, polyethylene glycol (PEG), a component in the 2 mRNA vaccines, is known to cause anaphylaxis. In addition, polysorbate 80, an ingredient in the Johnson & Johnson vaccine, may cause anaphylaxis and reactivation with PEG.

Patients with an allergic reaction to PEG should not be given the mRNA vaccines, but vaccination with adenovirus vector vaccines may be considered.

The CDC currently recommends adenovirus vector vaccines as a substitute for the second dose of mRNA vaccine for patients who have received a response to the first dose, waiting at least 28 days between doses.

According to CDC guidelines, polysorbate allergens are not contraindicated against mRNA vaccines, but are cautionary and due to potential cross-reactive hypersensitivity between ingredients in mRNA and adenovirus vaccines, co-administration should be considered. -consultation. Also, for patients with polysorbate allergy, there should be a minimum observation time of 30 minutes after mRNA vaccination.

There are very limited, but growing, data on the risk to patients with a history of allergic reactions associated with idiopathic mast cell activation syndrome / anaphylaxis.

Conventional data show that allergic reactions to all vaccines are very rare, with anaphylaxis estimated at 1.31 in 1 million doses. For the first 2 COVID-19 vaccines that received Emergency Use Authorization (EUA) from the FDA, anaphylaxis levels as Jan 29 were at 5 per million with the Pfizer-BioNTech mRNA-based vaccine and 2.5 per million for its Moderna vaccine.

Anaphylaxis levels have not yet been reported for the recently approved Johnson & Johnson vaccine.