According to advice from the UK authorities, anyone who has ever experienced anaphylactic reactions to food, drugs or vaccinations should not be vaccinated with the new Pfizer/BioNTech vaccine BNT162b2 for the time being.
The people who experienced anaphylaxis should actually not have been vaccinated in the first place because they had a history of anaphylaxis. According to information provided by the UK authorities, the Pfizer/BioNTech vaccine should not be administered to people who have previously experienced an anaphylactic reaction to vaccines or vaccine components (England NHS 20). This risk could have been detected with an allergy test before vaccination, which would have prevented the anaphylactic reactions.
How should people with allergies proceed?
According to the German allergy societies AeDA, DGAKI and GPA, allergic reactions to vaccines are on the whole very rare. Studies indicate figures between one and a maximum of 300 cases per million vaccinations (Klimek 2020).
“If they have no history of anaphylaxis, people with allergies will react to the vaccine just like people without allergies”, says Prof. Torsten Zuberbier. The largest study to date on the Pfizer/BioNTech vaccine demonstrates that the incidence of allergic reaction is similar regardless of whether the vaccine or a placebo is administered (Polack 2020).
How should you proceed if you have had anaphylaxis?
In order to prevent further anaphylactic reactions, doctors must ask each patient about potential severe allergic/anaphylactic reactions before vaccinating them.
“Anyone who has had an anaphylactic reaction in the past must inform the doctor or health care professional giving the vaccination”, says Zuberbier.
According to the German allergy societies, even patients who have had severe allergic reactions in the past can be vaccinated. However, they must be given the right allergy medicines beforehand. In addition, they should only be vaccinated by doctors experienced in treating anaphylactic reactions. But in order to assess whether this is possible, we will have to wait for the results of the ongoing investigation into the causes behind the anaphylaxis cases in the UK.
How does the allergy occur?
The exact cause of the reactions is still unknown.
The Pfizer/BioNTech vaccine BNT162b2 contains ten ingredients. The most important one is mRNA, an active ingredient that instructs the body to make coronavirus spike proteins to which the immune system then develops antibodies. In addition, there are nine other substances that preserve the vaccine and make it usable. None of these nine substances commonly triggers allergies.
The only one of the nine substances known to trigger any allergies at all is polyethylene glycol (PEG). Allergic reactions to PEG are likely underdiagnosed – PEG is therefore also considered a ‘hidden’ allergen.
Another chemical substance – polysorbate 80 – is very similar in structure to PEG in certain places and can therefore trigger cross-reactions (Stone 2018). The vaccine does not contain polysorbate 80. It is used as an emulsifier in pickled foods, nutritional supplements, ice cream and some important medicines, such as biologics.
What should I do if I have asthma?
Asthmatics, whether allergic or non-allergic, have neither an increased risk of coronavirus infection nor an increased risk of particularly severe disease after becoming infected.
People with asthma can receive a coronavirus vaccination in the same way as non-asthmatics.
If they are in the recommended group, they should have a flu vaccination, regardless of whether they have received a coronavirus vaccination. The flu vaccine does not protect against the coronavirus, but it does not reduce the efficacy of the coronavirus vaccine.
The two vaccinations should be given at least seven days apart in case of potential side effects from either vaccine.
According to what we currently know, asthma patients can continue to use any of the previous treatment methods for asthma.
This includes biologics, which are used to treat
- severe asthma
- atopic dermatitis
- chronic non-specific urticaria
- chronic rhinosinusitis with nasal polyps
All asthmatics should continue to use the same medicines as they did before the coronavirus.
Information on the anaphylaxis cases in the UK
Two employees of the British National Health Service NHS experienced severe allergic reactions minutes after the vaccination. They had to receive emergency treatment. Both were known to have had an anaphylactic shock in their medical history. They also carried an adrenaline autoinjector. The two patients are recovering well, according to NHS chief Stephen Powis. In the US, two workers in Alaska experienced similar reactions after vaccination.
Overall, the reactions are rare: In the UK, almost 138,000 people received the first dose of the vaccine in the first seven days. It was there that the Pfizer/BioNTech coronavirus vaccine was the first in the world to be approved. It has been used extensively in the vaccination programme in the UK since 2020 December 15.
Since then, every vaccinated patient in the UK has been monitored for 15 minutes after vaccination so that medical staff can intervene immediately in the event of a reaction. In addition, all patients from now on will be asked about their allergy status before vaccination. The patient information also mentions the possibility of allergic reactions.
Anaphylaxis Campaign. Pfizer Covid-19 Vaccine and Allergies. Last download on 19 December 2020
Centers for Disease Control and Prevention. Interim Clinical Considerations for Use of mRNA COVID-19 Vaccines Currently Authorized in the United States. Last download on 19 December 2020
An overview of the exact ingredients of the vaccine can be found here.
England NHS: Patient Group Direction for COVID-19 mRNA vaccine BNT162b2 (Pfizer/BioNTech) – NATIONAL COVID-19 VACCINATION PROGRAMME. England NHS. 2020. Last download on 4 January 2021
Katherine J. Wu Here’s What People With Allergies Should Know About Covid Vaccines. New York article dated 19 December 2020. Last download on 19 December 2020
Klimek L et al. Severe allergic reactions after COVID-19-Vaccination with the Pfizer/BioNTech Vaccine in Great Britain and USA. Position Statement of the German Allergy Societies: Medical Association of German Allergologists (AeDA), German Society for Allergology and Clinical Immunology (DGAKI) and Society for Pediatric Allergology and Environmental Medicine (GPA). Allergo Journal International 2020. (In German)
Stone CA et al. Immediate Hypersensitivity to Polyethylene Glycols and Polysorbates: More Common Than We Have Recognized.
The journal of allergy and clinical immunology In practice. 2019;7(5):1533-40.e8.
Polack FP et al. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine. NEJM 2020;383:2603-15