By Sarah Toy and Joanna Sugden
Severe allergy sufferers say they are confused about whether they should get the Covid-19 vaccine made by Pfizer Inc. and BioNTech SE, and public-health authorities on both sides of the Atlantic are offering conflicting advice.
The U.K.'s medical regulator warned people with severe allergies to food, vaccines or medicine against getting the Pfizer-BioNTech vaccine after two severe allergic reactions among vaccine recipients in that country.
Two health-care workers in Alaska also experienced allergic reactions after receiving the vaccine, one which required hospitalization. In contrast to the U.K. regulator, the U.S. Food and Drug Administration and Health Canada have advised only against administering the shot to people with a known history of severe allergic reaction to any component of the vaccine itself.
Some patients in the U.S. and U.K. said they were puzzled and unsure about what advice to follow.
"I'm definitely concerned about it," said Abigail Espinoza, a 43-year-old mother of three and architectural design student in Astoria, Ore., who said the U.K. incidents worried her. She has severe allergies to pistachios and penicillin, which can lead to issues with her breathing. To treat possible allergic reactions, she carries an epinephrine auto-injector.
Ms. Espinoza, who isn't among the first group of people being vaccinated, said she isn't planning to receive the Pfizer-BioNTech vaccine until there are more data and research available on the vaccine and people with allergies. She also wants to consult an allergist before getting a shot.
Doctors say they are fielding a flood of questions from patients with various types of allergies, who say they aren't sure what to do once they become eligible.
Doctors fear that the cases of severe reaction and the contradictory advice around allergies will discourage patients from getting the vaccinated, as the Pfizer-BioNTech vaccine rolls out, with Moderna Inc.'s Covid-19 vaccine likely to come soon.
Niraj Patel, an allergist and chair of the American College of Allergy, Asthma and Immunology Covid-19 Task Force, said he has been getting a lot of questions about whether people with allergies are at higher risk of having a serious reaction to the vaccine. "They want to know whether it's safe to receive," he said.
Dr. Patel and other allergy experts in the U.S. have been telling concerned patients that only people with a history of severe allergic reactions to a specific component of the vaccine -- particularly a compound called polyethylene glycol -- shouldn't receive the vaccine. Otherwise, having a severe allergy to foods or oral medications doesn't increase your chance of an allergic reaction to the vaccine, he said.
Allergists find that some people can have allergies that are related to each other. For instance, people who are allergic to one type of nut may also be allergic to other types of nuts because they contain similar chemical structures, something known as cross-reactivity, Dr. Patel said.
"There doesn't seem to be any cross-reactivity between agents that are in the Covid vaccine and other common proteins that cause anaphylaxis, such as food or drugs," he said. Anaphylaxis is the most severe form of an allergic reaction, which can result in airway closure and death.
Before the U.K.'s rollout of the Pfizer vaccine on Dec. 8, that country's advice was in line with its guidance for all vaccines and mirrored Pfizer and BioNTech's recommendations for their shot: Those with allergies to the vaccine or its components shouldn't take it.
Chris Whitty, chief medical officer for England, said the U.K. altered its advice based on reactions in the real world that hadn't happened in the clinical trials. That has led to an improvement over time in the number of cases of anaphylaxis after injections, Mr. Whitty said Wednesday.
Sometimes the ingredient that triggered the reaction -- the allergen -- isn't known, said the U.K.'s Medicines and Healthcare Products Regulatory Agency. "That's why, as a precautionary measure, our current advice is that any person with a history of immediate-onset anaphylaxis to a vaccine, medicine or food should not receive the Pfizer-BioNTech vaccine," an MHRA spokeswoman said. "Further investigation into these cases is ongoing," she added.
Professor Saad Shakir, director of the drug safety research unit in the U.K., said the decision to broaden the restrictions on vaccine recipients was "the correct risk-minimization action."
"It is reassuring that the decision was made and communicated so promptly," he said.
Anaphylaxis after vaccines generally happens only around once per every million doses, according to the ACAAI. People who have had severe allergic reactions, such as anaphylaxis, to any component in the Pfizer-BioNTech vaccine shouldn't receive the vaccine, according to the FDA and the U.S. Centers for Disease Control and Prevention. The vaccine components can be found on the FDA's website.
People with severe allergies to any other vaccine or injectable may receive the vaccine, but should speak with their medical providers beforehand about weighing the risks of an allergic reaction with the benefits of receiving the vaccine, the agency advises. And there is no reason why people who have a history of mild or severe allergic reactions to food, pets, oral medications or environmental allergens such as pollen shouldn't receive the vaccine, the CDC says.
The CDC also says all recipients of the vaccine should be observed for 15 minutes after vaccination to monitor for possible adverse reactions. People with a history of anaphylaxis should be observed for 30 minutes after vaccination, it says.
Pfizer and BioNTech have said that people with severe allergic reactions to the vaccine or its component parts shouldn't receive the shot. The vaccine's clinical trials didn't include people with that profile, according to the companies.
Anaphylaxis wasn't observed during clinical trials of the Pfizer-BioNTech vaccine, though 0.63% of a subset of vaccinated participants in the later-stage trials had so-called hypersensitivity-related adverse events, which could have been allergic reactions. In the placebo group, 0.51% had these reactions.
Moderna said that there had been one anaphylactic reaction in a vaccine recipient in its study, but it occurred two months after the second dose in a person with a history of asthma and allergy to shellfish. Allergists say it is unlikely for anaphylactic reactions to happen in such a delayed manner; most reactions would occur within minutes. The company said it plans to continue monitoring such events.
Some U.S. vaccine and allergy experts said they disagreed with the U.K.'s decision to bar all people with severe allergies to food, medicine or vaccines from getting vaccinated. They said such a policy is too broad, given that there were only two cases of severe allergic reactions in the U.K. out of 138,000 doses given in the first week.
"You're talking about eliminating tens of millions of people" from the vaccination program if you bar people with severe allergies to food or medicines from getting the injection, said Paul Offit, a vaccine expert at the Children's Hospital of Philadelphia who is on the FDA's Covid-19 vaccine advisory panel. The FDA said it was investigating the two allergic reactions in Alaska.
People with allergies need to understand that they are generally at the same risk of having an allergic reaction to the vaccine as anyone else, he said. "We need to offer people some solace that this is not going to be a problem for them," Dr. Offit said.
Write to Sarah Toy at email@example.com and Joanna Sugden at firstname.lastname@example.org
(END) Dow Jones Newswires
December 18, 2020 11:33 ET (16:33 GMT)Copyright (c) 2020 Dow Jones & Company, Inc.