• Samantha Marmet

“But What if I’m Allergic?” Evaluating COVID-19 Vaccine Side Effects

Updated: Mar 26, 2021



In December 2020, an alarming New York Daily News article titled “Boston doctor ‘scared to death’ by an allergic reaction to Moderna COVID vaccine” garnered attention from both online readers and the medical community. One doctor’s severe allergic reaction to the COVID-19 mRNA vaccination raised questions about potential side effects of the vaccination and whether or not it was safe for public distribution. Are you worried about allergic reactions? Don’t be — the Centers for Disease Control and Prevention support vaccine distribution and have issued guidelines for vaccination distribution centers to aid in the case of emergency allergic reaction.


An article published in the Journal of the American Medical Association (JAMA) called "Reports of Anaphylaxis After Receipt of mRNA COVID-19 Vaccines in the US" analyzes reports of anaphylaxis after administration of Pfizer and Moderna vaccines. Defined by the Mayo Clinic, anaphylaxis is a potentially life-threatening allergic reaction that causes your body to go into shock. Symptoms include nausea, vomiting, rashes, and difficulty breathing. In extreme cases, without medical intervention, anaphylaxis can result in unconsciousness or death.


Original estimates of the incidence of anaphylaxis were 11.1 cases per million doses of Pfizer and 2.5 cases per million doses of Moderna. However, millions of COVID-19 vaccinations have been administered since these early statistics. Between December 14, 2020, and January 18, 2021, more than 17.5 million doses were administered in the US, and the Centers for Disease Control and Prevention identified only 66 cases of anaphylaxis reactions.


21 of these 66 cases, or 32% of patients, report a history of anaphylactic reactions from other exposures, including other vaccines, penicillin, latex, and tree nuts. 92% of these 66 reported cases were treated with a shot of epinephrine, an injection used to treat severe allergic reactions. There are no reported deaths from anaphylaxis after the mRNA vaccination.


Anaphylaxis after vaccinations is a rare event. Of those who go into anaphylactic shock, the majority have a prior history of severe allergic reactions. However, this does not mean someone with no prior history cannot have an anaphylactic reaction. This is why the Centers for Disease Control and Prevention are recommending a 15 to 30-minute post-vaccination observation period for all vaccination distribution centers. This means that after receiving your COVID-19 vaccine, you will sit for 15 to 30 minutes under medical supervision so that you can be treated immediately if an anaphylactic reaction were to occur.


Based on the most recent statistics, medical professionals are estimating rates of anaphylaxis post-vaccination to be 4.7 cases per million doses of Pfizer and 2.5 cases per million doses of Moderna. Dr. Dough Paauw, internist and chair of Patient-Centered Education at the University of Washington School of Medicine, estimates that eventually, the allergic reaction rate will become 1 per 1 million people. To put this in perspective, common medications like penicillin will have higher rates of anaphylaxis than the mRNA vaccination. Regardless of your history with allergic reactions, it is best to speak to a healthcare provider before taking the vaccine if you have any concerns about anaphylaxis.


 

Speaking Plainly:

  • A very small percentage of people do get allergic reactions from taking the mRNA vaccines, but there are no reported deaths from these allergies.

  • As a result, the CDC recommends a 15 to 30-minute post-vaccination observation period for all vaccine distribution centers.

  • If you are concerned about getting an allergic reaction to the vaccines, it is best to speak to a healthcare provider before you take the vaccine.