#38: COVID-19 Vaccine Allergies & Testing: everything you need to know

Dr. Lacey Robinson joins Kortney and Dr. G to discuss where we are at with understanding allergic reactions to the two mRNA COVID-19 vaccines (Pfizer-BioNTech and Moderna). 

 

Dr. Robinson outlines the current theories on what may be causing these allergic reactions, who should get an allergy test before having the vaccine, and what the other symptoms that could appear like an allergic reaction to the vaccine are. 

 

Important note about this episode, as things are changing rapidly in what we know about the COVID-19 vaccines:

• This episode was recorded on January 21, 2021, released January 26, 2021
• Discussions about the COVID-19 vaccines refer to the Pfizer-BioNTech vaccine and Moderna vaccine, both mRNA vaccines. 

What we cover in this episode:

• How common are vaccine allergies? 
  • Stat: 1.31 cases of reactions per 1 million doses given.
  • The CDC reviewed the Pfizer vaccine given in December 2020. They found 21 cases of confirmed anaphylaxis in 1.89 million does, which is 11.1 cases per 1 million does. Only 7 of the 21 had a history of anaphylaxis.
• What are the symptoms that can be mistaken for an allergic reaction when receiving the COVID-19 vaccine?
• What studies are in the pipeline to look at allergy to the COVID-19 vaccines, specifically mRNA vaccines. 
• Types of anaphylactic reaction:
  • IgE medicated reaction
  • Non-IgE mediated: Mast cell activation or compliment mediated anaphylaxis
• Some symptoms that you can expect when getting the COVID-19 Vaccine:
  • Large local reaction
  • Tired
  • Muscles aches and pains
  • Headaches
  • Fever
• Timing of an allergic reaction (true allergy) versus other typical symptoms coming from the vaccine. 
• What they suspect are the reasons that people are having an allergic reaction to the COVID-19 vaccine
  • Note mRNA vaccines do not contain any food allergies.
  • Polyethylene glycol (PEG) is the suspected allergen. PEG is a common ingredient in many medical products. A very rare allergy 4 cases per year. 
• Could you be reacting to the mRNA that you are making from the vaccine?
• Who should consider getting an allergy test for the COVID-19 vaccine. 
• How are people being treated if they are having an allergic reaction to the COVID-19 vaccine?
• If you had a reaction to the vaccine or you have a PEG allergy, what are the steps involved in evaluating if you can get the COVID-19 vaccine.
• How allergist test PEG allergy. 
  • What is the likelihood of a false negative test result?

Resources:

• Allergic Living article Kortney quotes: https://www.allergicliving.com/2021/01/03/likely-more-than-one-cause-for-covid-19-vaccine-reactions/
• Our episode about understanding the COVID-19 Vaccines: https://www.itchpodcast.com/post/episode-37