According to the CDC, about one in 10,000 people who have received the Pfizer-BioNTech COVID-19 vaccine has experienced severe allergic reactions. The US disease policeman, however, stressed that the benefits of vaccination far outweigh the risks.
According to Nancy Messonnier, head of the CDC, in December 2020, 21 cases of anaphylaxis after the administration of more than 1,800,000 injections were reported , an average rate of 11.1 cases of anaphylaxis per million doses administered. This is 10 times the rate of anaphylaxis for a million doses of influenza vaccine.
According to Messonier, these cases of anaphylaxis were still extremely rare. And in the context of the COVID-19 pandemic, people have an interest in getting vaccinated , as this virus poses a much greater danger to their health.
Arrangements have also been put in place to ensure that health workers can treat anaphylaxis when the vaccine is administered.
The figures on these allergy cases linked to Pfizer's vaccine
A total of 21 cases of anaphylactic reaction in people aged 27 to 60 years have been reported, with an average age of 40 years and a female majority. Except for two cases, all the others were treated with epinephrine. And according to scientists, the onset of symptoms occurs between 2 to 150 minutes, with an average of 13 minutes, in patients.
Four cases of hospitalization, including three in intensive care, have been reported. The other patients were taken care of in an emergency department. After treatment, a large majority of patients were discharged home or recovered at the time of the study. Fortunately, no deaths have been reported.
For information, the symptoms of allergic reactions reported were a rash, a feeling of blockage in the throat, tongue or swollen lips, hives, difficulty in breathing, hoarseness, nausea and a persistent dry cough.
Tracking down what caused these allergic reactions
So far, the mRNA-based vaccines developed by Pfizer and Moderna are the only vaccines authorized in the United States.
The Moderna vaccine was cleared a week after Pfizer's shot. However, data indicating the rate of anaphylaxis for Moderna is still insufficient and it is not known whether a significant difference between the two vaccines will emerge.
The presence of the polyethylene glycol compound (PEG) that can be found in products for daily use such as laxatives, shampoos and toothpastes is a preliminary hypothesis to explain these allergic reactions. For clarification, this compound has never been used before in an approved vaccine, but has been added as a protective wrap around the main vaccine ingredient, mRNA.