Doctor explains COVID-19 vaccine allergic reactions in UK

British regulators are warning anyone who has a history of severe allergic reactions to food, a medicine, a vaccine, or someone who has been prescribed an Epipen by their doctor should refrain from getting the Pfizer vaccine for the time being.

According to Dr. Amesh Adalja, Infectious Disease Expert at Johns Hopkins University, the symptoms could be similar to what a person would experience if they had a reaction to food.

READ MORE: UK investigates possible allergic reactions to COVID-19 vaccine shot

“British regulators did state that these individuals had anaphylaxis which is a severe allergic reaction and it’s characterized by swelling, shortness of breath, sometimes throat tightening, and a rash. The other reactions people have from this vaccine are the common ones you would expect like muscle aches and pains, fevers and chills, and headaches,” said Adalja.

At this time, it is not clear what exact component of the vaccine triggered those individuals or if it was coincidental. That is being investigated.

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Dr. Adalja is reminding everyone that the Pfizer vaccine is one of dozens expected to roll out so there may be another that is more suitable for people with a history of allergic reactions. He adds we can expect to continue seeing rare side effects as more people get vaccinated.

“We do see allergic reactions like this to about 1 in 1.4 million so it’s not something that’s unheard of and as we vaccinate more and more people,” said Adalja. “In the Phase 3 clinical trial, you have tens of thousands of people. Now, we’re going to be vaccinating a million so side effects and adverse reactions that occur one in a million are going to be real numbers when you start vaccinating a billion people.”

As FDA approval of the vaccine is on the horizon here in the United States, Dr. Adalja said it is too early to know for certain if any advisory will be put out in response to what happened in Britain.

“I suspect the FDA will issue some guidance in regard to what happened in the United Kingdom for our own vaccination roll out, but what I’ve seen so far, is that this is a very safe and highly effective vaccine and I wouldn’t hesitate to get the vaccine today if it were available to me,” said Adalja.