According to the American Institute of Allergy, Asthma and Immunology, this anaphylactic shock can cause swelling in the throat, difficulty breathing and difficulty swallowing. Anaphylaxis is an over-reaction of the body’s immune system, which the UK National Health Service describes as severe and sometimes life-threatening.
UK regulators have initially issued a statement that anyone with a history of severe allergies to a vaccine, medicine or food should not be vaccinated, according to Reuters news agency.
The Pfizer Group excluded people with a history of significant adverse reactions to the vaccine or its ingredients from end-stage trials.
US health regulators are expected to soon consider the emergency licensing of the Pfizer vaccine following its advisory meeting on December 10.
Moncef Slaoui, who is leading the US government’s vaccine development efforts, said on December 9 he expects allergic reactions in the UK to be considered in the US authorization process. According to him, people with known severe allergic reactions should probably not get the vaccine until better understanding.
Professor Stephen Evans of the London School of Hygiene and Tropical Medicine said: “For the general public, this doesn’t mean they need to worry about getting vaccinated. It is wise for anyone who has had a severe allergic reaction to delay getting vaccinated until the cause of the allergic reaction is clarified. “
Peter Openshaw, a professor of experimental medicine at Imperial College London, praised the way reactions are handled. He said: “The fact that we know very early about these two allergic reactions and the regulator has taken action to provide preventive advice suggests that the surveillance system is working well.”
American health experts say allergic reactions reported by British health care workers when getting Covid-19 vaccinated are likely to be discussed before the US Food and Drug Administration ( FDA) permits the Pfizer vaccine to be used in the US.
Moncef Slaoui, chief scientific advisor for the White House’s Warp Speed Campaign, said at a press conference on December 9: “This is not surprising because people with underlying health conditions are often not included in clinical trials.”
On December 10, FDA will convene a meeting of the Vaccine and Related Biological Products Advisory Committee (VRBPAC) to review the emergency licensing of Pfizer vaccines in the US. If the meeting goes well, the committee will vote through the vaccination.
Dr. William Schaffner, professor of infectious diseases at Vanderbilt University Medical Center, said that allergic reactions will not affect vaccine licensing. That is the kind of problem the committee “deals with often because so many vaccines are associated with allergic reactions in a small proportion of the population”.