When reports of severe allergic reactions among recipients of Covid-19 vaccines surfaced, Angelina Giunta became concerned.
Although Giunta, 61, of Brooklyn, New York, was desperate to get the vaccine quarantined after a year, in 2017 she had two severe allergic reactions to medication during cancer treatment.
“I want to get the vaccine because I want to get on with my life,” Giunta said. “But I was very worried.”
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Two ingredients in the Covid-19 vaccines, polyethylene glycol and polysorbate 80, have been suggested as possible culprits in anaphylactic reactions associated with Covid-19 vaccines. (Anaphylaxis is a serious, life-threatening allergic reaction.) To date, however, the link has not been definitively established.
However, some allergy clinics in the US have still shown that they are capable of testing patients for allergies to the ingredients.
According to many experts, these tests can waste time and resources – especially since such allergies are incredibly rare.
Colleagues of mine who have been practicing allergies for 20 to 30 years can count the number of patients they have seen with polyethylene glycol reactions on the one hand.
“Colleagues of mine who have been allergic for 20 to 30 years can count the number of patients they have seen with polyethylene glycol reactions on one hand,” said Dr. Paul Williams, an allergist at the Northwest Asthma and Allergy Center in Seattle, said. and clinical professor of pediatrics at the University of Washington.
In fact, it is likely that the vast majority of Americans have already been exposed to polyethylene glycol or polysorbate 80.
Polyethylene glycol is a common active ingredient in over-the-counter laxatives. Pfizer-BioNTech and Moderna use it in their vaccines as a protective layer for messenger RNA, or mRNA, pieces of genetic code used to teach cells how to recognize and fight the virus that causes Covid-19.
And polysorbate 80 is found everywhere in the typical American diet, found in chewing gum, ice cream, puddings and other foods. It is used as an emulsifier to make products creamier. It is also an ingredient in the Johnson & Johnson Covid-19 vaccine that has been identified as a possible allergen – although no allergic reactions have been reported to Johnson & Johnson vaccine recipients to date.
“There is nothing special about these vaccines in terms of allergic diseases or anaphylaxis,” says Dr. Mitchell Grayson, chair of the Asthma and Allergy Foundation of America’s Medical Scientific Council. “Why don’t we see more people with polyethylene glycol or polysorbate allergy in general?”
Serious allergic reactions to the Covid-19 vaccine have occurred at 2 to 5 people per million vaccinated in the United States, the Centers for Disease Control and Prevention said in a statement to NBC News. “Fortunately, vaccination providers have medicines available to treat patients who experience anaphylaxis after vaccination effectively and immediately.”
In addition, the selection and monitoring of such reactions is included in the vaccination protocol of Covid-19: this is why vaccine recipients are asked in advance if they have had a severe allergic reaction to a vaccine and why they are told to wait until 15 to 30 minutes after receipt of the vaccine, so that if a medical reaction occurs, medical staff can respond on hand.
Grayson said the biggest problem with Covid-19 vaccines is not allergies, it’s hesitation. Nearly a third of those who took part in a recent survey by the Kaiser Family Foundation said they should rather wait to see what happens to others who get the vaccine before rolling up their sleeves.
“My fear is that it all just helps to feed on it,” Grayson said, referring to testing for allergies to Covid-19.
Who, if anyone, needs a test?
Charleston Allergy and Asthma in South Carolina is a clinic testing polyethylene glycol and polysorbate 80. The tests are done by scratching a small amount of the substance in the skin of a person and noting reaction, such as redness or itching.
‘At this stage we do not know exactly what [vaccine] components cause reactions in all of these different individuals, “said Dr. Meredith Moore, a physician in the clinic.” But polyethylene glycol and polysorbate are the most likely culprits if you look at the ingredients in the two vaccines. “
None of the tests administered to Moore patients so far have been positive.
Moore said most people with allergies do not have to worry about the possible reactions to Covid-19 vaccines.
Moore recommends not being tested for people who carry emergency epinephrine for peanut, insect or other allergies. She said allergy testing for polyethylene glycol or polysorbate 80 should be reserved for people with a history of allergic reactions without any known cause.
John Grabenstein, a former executive director of medical matters for vaccines at Merck and a former immunologist at the Department of Defense, said there was no evidence that the tests posed the risk of any allergic reactions to the Covid-19 vaccine. does not decrease.
As the ingredients have not been proven to be causes of Covid-19 vaccine allergic reactions, this does not necessarily mean that a negative allergy test for polyethylene glycol or polysorbate 80 will spare an allergic reaction to the vaccine. A positive test should not prevent anyone from getting the Covid-19 vaccine, experts say.
“The vast majority of the public – even people with pollen allergy, people with penicillin and bee allergy – do not have to worry about vaccination,” Grabenstein said.
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Dr Cascya Charlot, who presents the tests in her practice at Allergy and Asthma Care in Brooklyn, agrees.
“I’m not advocating that everyone should do skin testing before they get the vaccine, absolutely not,” Charlot said.
She sees testing as a way to allay fears of allergic reactions to the Covid-19 vaccine.
“It’s an incentive for public health, as far as we can see, to try to vaccinate people,” Charlot said. “We do not want to worry about a possible reaction to the vaccine.”
None of the allergy tests Charlot did for polyethylene glycol or polysorbate 80 came back positive.
The harm in relying on such tests, according to Grayson, is that someone “should avoid a vaccine that they might otherwise receive.”
“You unnecessarily exclude people from a vaccine, or you allow them to continue with a vaccine, without knowing for sure whether they will have an anaphylactic reaction again,” Grayson said.
The one positive effect seems to be peace of mind.
Giunta, one of Charlot’s patients, tested negative and was looking forward to her Covid-19 vaccine.
“I want to get on with my life and journey, you know,” Giunta said, “doing the normal things I did before.”
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