LONDON (AP) — Britain’s medical regulator warned Wednesday that people with a history of serious allergic reactions shouldn’t get the COVID-19 vaccine from Pfizer and BioNTech, and investigators looked into whether two reactions on the first day of the U.K.’s vaccination program were linked to the shot.
The advice was issued on a “precautionary basis,” and the people who had the reactions had recovered, said professor Stephen Powis, medical director for National Health Service in England.
Pfizer and BioNTech said they were working with investigators “to better understand each case and its causes.″
Also on Wednesday, Canada’s health regulator approved the vaccine, with Dr. Supriya Sharma, chief medical adviser at Heath Canada, calling it “a momentous occasion.”
Canada is set to receive up to 249,000 doses this month and Canadian officials expect to start administering them next week as soon after they are shipped from Belgium on Friday.
Britain’s Medical and Healthcare Products Regulatory Agency has said people should not receive the shot if they have had a significant allergic reaction to a vaccine, medicine or food, such as those who have been told to carry an adrenaline shot — such as an EpiPen or other similar devices — or others who have had potentially fatal allergic reactions. The medical regulator also said vaccinations should be carried out only in facilities that have resuscitation equipment.
Such advice isn’t uncommon; several vaccines already on the market carry warnings about allergic reactions, and doctors know to watch for them when people who’ve had reactions to drugs or vaccines in the past are given new products.
The two people who reported reactions were NHS staff members who had a history of significant allergies and carried adrenaline shots. Both had serious reactions but recovered after treatment, the NHS said.
Stephen Evans, a professor of pharmacoepidemiology at the London School of Hygiene & Tropical Medicine, said the regulator had done the right thing, but the general public shouldn’t be worried about getting the vaccine.
“For the general population, this does not mean that they would need to be anxious about receiving the vaccination. One has to remember that even things like Marmite can cause unexpected severe allergic reactions,” he said, referring to the food spread that is made from brewer’s yeast.
Dr. Ashish Jha, dean of the school of public health at Brown University, said he would advise patients who have had severe allergic reactions to other medicines or foods to delay vaccination if they can while the two cases in the U.K. are investigated. He would extend that advice to people who carry EpiPens.
“The cautionary approach is to say to people who have had severe reactions to other things, ‘just hold,’” Jha said, adding: “There is going to be a deep dive into these two people who got an allergic reaction” to the vaccine.
He added that because the vaccine is so high-profile, “every little thing that happens all the time is going to get magnified. We should talk about it, we should be honest with people, but we should put it into context and help people understand … there is a small proportion of people who have an allergic reaction to almost any medicine.”
The comments came a day after Britain rolled out its mass vaccination program amid efforts to control a pandemic that has killed more than 62,000 people across the country. The MHRA gave an emergency authorization to the Pfizer-BioNtech vaccine last week, making Britain the first country to approve its widespread use.
Even in nonemergency situations, health authorities must closely monitor new vaccines and medications because studies in tens of thousands of people can’t detect a rare risk that would affect 1 in 1 million. Authorities have not said how many people have received the shot in Britain so far, but they plan to give 800,000 doses in the first phase, which will target people over 80, nursing home staff and some NHS workers.
Late-stage trials of the vaccine found “no serious safety concerns,” Pfizer and BioNTech said. More than 42,000 people have received two doses of the shot during those trials.
Detailed data from the vaccine’s trials showed potential allergic reactions in 0.63% of those who received the vaccine, compared with 0.51% of those who received the placebo. Reviewers from the U.S. Food and Drug Administration called this a “slight numerical imbalance.”
Documents published by the two companies showed that people with a history of severe allergic reactions were excluded from the trials, and doctors were advised to look out for such reactions in trial participants who weren’t previously known to have severe allergies.
As part of its emergency authorization for the vaccine, the MHRA required health care workers to report any adverse reactions to help regulators gather more information about safety and effectiveness.
The agency is monitoring the vaccine rollout closely and “will now investigate these cases in more detail to understand if the allergic reactions were linked to the vaccine or were incidental,” Powis said. “The fact that we know so soon about these two allergic reactions and that the regulator has acted on this to issue precautionary advice shows that this monitoring system is working well.”
Dr. June Raine, head of the medical regulatory agency, informed a parliamentary committee about the reactions during previously scheduled testimony on the pandemic.
“We know from the very extensive clinical trials that this wasn’t a feature” of the vaccine, she said. “But if we need to strengthen our advice, now that we have had this experience in the vulnerable populations, the groups who have been selected as a priority, we get that advice to the field immediately.”
Margaret Keenan, the first person to get the vaccine in the U.K., was discharged Wednesday from University Hospital Coventry, where she had been undergoing a heart checkup when she was given the shot.
“I feel great and I’m so pleased to be able to go home and to spend some quality time with my family,” the 90-year-old former shop clerk said in a statement released by the NHS.
—-
Associated Press writers Frank Jordans in Berlin, Lauran Neergaard in Alexandria, Virginia, Rob Gillies in Toronto and David Koenig in Dallas contributed.
—-
Follow AP’s coverage at https://apnews.com/hub/coronavirus-pandemic and https://apnews.com/UnderstandingtheOutbreak
EXPLAINER: Allergic reactions to vaccines rare, short-lived
Vaccines can sometimes cause allergic reactions, but they are usually rare and short-lived.
British regulators are looking into reports of allergic reactions in two people who received the new Pfizer COVID-19 vaccine Tuesday, the first day of a vaccination program. In the meantime, they’re telling people to skip the vaccine if they’ve had a history of serious allergic reactions.
A look at allergic reactions to vaccines:
HOW OFTEN DO THEY HAPPEN?
Allergic reactions can occur with numerous vaccines and experts say they are not unexpected.
In the Pfizer-BioNTech study of 42,000 people, the rate was about the same in those who got the coronavirus vaccine versus those who got a dummy shot. U.S. Food and Drug Administration reviewers who examined the study’s safety data found that 137 — or 0.63% — of vaccine recipients reported symptoms suggestive of an allergic reaction, compared to 111 — or 0.51% — in the placebo group.
A 2015 study in the U.S. examining the rate of anaphylaxis — a severe, life-threatening allergic reaction — found that it occurred about once per every million vaccine doses. The study evaluated children and adults who got vaccines against numerous diseases, including polio, measles and meningitis.
“For the general population this does not mean that they would need to be anxious about receiving the vaccination,” said Stephen Evans, a vaccines expert at the London School of Hygiene and Tropical Medicine.
He noted that even common foods can provoke severe allergic reactions.
WHY DO THESE REACTIONS HAPPEN?
Scientists say people can be sensitive to components in the shot, like gelatin or egg protein, or to the vaccine itself. People with egg allergies are sometimes advised not to get the flu shot, since that vaccine is mostly grown in chicken eggs.
Common symptoms of an allergic reaction include a rash, skin irritation, coughing or trouble breathing.
The exact ingredients used in Pfizer’s new COVID-19 vaccine are proprietary and are not publicly disclosed. The vaccine uses a new technology, and is coated in lipid nanoparticles, which have been used in drugs.
Some people react to almost any drug or vaccine, said Dr. Ashish Jha, dean of Brown University’s school of public health. The key is whether reactions to the vaccine are more common or more severe __ and that doesn’t appear to be the case so far, he said.
WHAT ARE OTHER SIDE EFFECTS?
Typical side effects for many vaccines include things like a sore arm from the shot, fever and muscle aches. In the Pfizer study, participants also reported fatigue, headache and chills.
More serious side effects are reported to regulators or health officials for further investigation. But it can often take time to determine if the vaccine caused the side effect or if the person just coincidentally received the shot before becoming ill.
As for the COVID-19 vaccine, “It’s just so high-profile that every little thing that happens all the time is going to get magnified,” said Jha.
“We should talk about it, we should be honest with people, but we should put it into context and help people understand,” he said. ”There is a small proportion of people who have an allergic reaction to almost any medicine.”