How safe are vaccines against the Covid-19 coronavirus? Here is the risk of allergic reaction

You may have seen headlines like “The healthcare worker had a severe allergic reaction after Pfizer’s Covid vaccine.” It makes sense to report such reactions as the Pfizer / BioNTech and Moderna Covid-19 vaccines are still fairly new. They have received Emergency Use Authorizations (EUA) in lieu of full market approval. Just because a vaccine has gone through the US Food and Drug Administration (FDA) US process does not mean that you should not follow up with people who get vaccinated later, in case new problems arise.

At the same time, put those case reports in the right context. A case report is a case report. It’s just one case. For example, just because a 25-year-old man had seizures while solving sudoku doesn’t mean he should hide his eyes every time he sees an empty 9 x 9 grid. And the fact that a man fell on his butt over an air hose and then inflated like a Macy’s Thanksgiving Day parade balloon doesn’t mean you need to steer clear of all the air hoses or keep your buttocks constantly squeezed. Whenever you hear about an adverse reaction to a vaccine or drug, the big question is how common is it?

Well, according to a report recently released by the Centers for Disease Control and Prevention (CDC), there were 21 cases of anaphylaxis out of 1,893,360 people who had received the first doses of the Pfizer-BioNTech Covid-19 vaccine. Anaphylaxis is a serious and life-threatening allergic reaction. Typical symptoms include rash, nausea, vomiting, shortness of breath, and shock. Anaphylaxis is a medical emergency. You don’t say to the other person during a date, “Oh, I’m having some anaphylaxis right now, but it happens here and there. Are you eating those last fries? “Instead, you need to treat anaphylaxis immediately with something like epinephrine to counteract the reaction. Otherwise, you may lose consciousness or die, which would prevent you from getting the last set of potato chips anyway.

Clearly, anaphylaxis is not a good thing. If someone asked you, would you rather deal with anaphylaxis or Anna Kendrick ?, choose Anna Kendrick. Kendrick may do something weird with your mug while singing “You’ll miss me when I’m gone,” but this probably won’t get you to the hospital. But again, how common is anaphylaxis after receiving the Covid-19 mRNA vaccine from Pfizer-BioNTech? Running the numbers from the CDC study well, which obtained data from the Vaccine Adverse Event Reporting System (VAERS), yielded the following number: 11.1 cases of anaphylaxis per million doses of vaccine administered.

If you were told that you have an 11 out of a million chance of getting something, what would your reaction be? Well when Lauren Holly’s character told Jim Carrey’s character in the movie Dumb and dumb that he had a one in a million chance of ending her, replied, “So you’re telling me there is a chance. Yes! “But for most, those chances wouldn’t seem that high at all.

“Any drug or health care product can cause allergic reactions,” explained Kimberly G Blumenthal MD MSc, Allergy Safety and Quality Officer at Massachusetts General Hospital. “So far, we don’t see a great risk of serious allergic reactions. It is about 1-2 out of 100,000 injections. There is a similar risk of serious reactions to the contrast agent we use every day for CT scans, cardiac catheterizations, and other procedures. “

Blumenthal tweeted the following graph to show the relative risks:

Also, it’s not like these serious allergic reactions haven’t been treated. Healthcare staff probably didn’t say, “Oh, that person over there? Yes, he has anaphylaxis. Kinda sucks. “No, they should be trained to handle such reactions. And since 71% of severe allergic reactions have occurred within 15 minutes of vaccination, wait at the vaccination site for that time after receiving the injection can help detect and properly treat such reactions.

The CDC report also mentioned 83 cases of non-anaphylactic allergic reaction after Pfizer-BioNTech Covid-19 vaccination during the same time period and 87% of them were classified as non-serious. This included itching, rashes, a scratchy throat sensation, and mild respiratory symptoms. These reactions tended to occur fairly soon after vaccination, an average of 12 minutes after injection. The vast majority, 85%, emerged half an hour after vaccination.

A history of allergies or allergic reactions can make you more likely to have an allergic reaction to the Covid-19 vaccine. In the CDC report, at least 67% of those who suffered an allergic reaction after vaccination reported a history of allergies or allergic reactions. This does not mean you should give up the vaccine just because you have a nut allergy or something else like the TV show. keeping up with the Kardashians. Your decision should depend on exactly what is causing your allergic reactions. The CDC on its website indicates that you should not receive the Covid-19 mRNA vaccine if you have already had a severe allergic reaction to any ingredient in the vaccine. So, for example, having a severe allergic reaction after the first dose of the vaccine may mean that you should not get the second dose. Similarly, a prior allergic reaction to polyethylene glycol (PEG), which is used to encapsulate mRNA in currently available Covid-19 mRNA vaccines, can present a problem. This also applies to polysorbate which is not found in Covid-19 mRNA vaccines but is closely related to PEG.

“For patients who have had severe allergic reactions in the past to a vaccine, polyethylene glycol, or polysorbates, a pre-vaccine visit with an allergist is recommended,” said Paige G. Wickner MD MPH, Medical Director of the Department of Quality and Safety . at Brigham and Women’s Hospital. “It is also important that patients who have a possible allergic reaction after dose 1 see an allergist before dose 2.”

Notify a qualified healthcare professional if you have any type of immediate allergic reaction (within four hours of vaccination). The CDC recommends speaking with your doctor when you experience any type of immediate reaction, regardless of whether it is severe, to determine what to do about it. subsequent vaccinations. Having an allergic reaction to the first dose of a vaccine does not necessarily preclude receiving a second dose.

Allergic reactions can evolve later as Blumenthal demonstrated in the following tweets:

As Blumenthal pointed out, these late reactions don’t necessarily mean that you don’t need to get vaccinated again, either. But it’s a good idea to talk to your doctor about what to do.

When it comes to other allergies, the CDC recommends “that people with a history of serious allergic reactions unrelated to vaccines or injectable drugs, such as food, pet, poison, environmental or latex allergies, get vaccinated. People with a history of allergies to oral medications or a family history of severe allergic reactions can also be vaccinated. “

“We understand that there can be confusion and mixed messages for allergy patients across the United States,” added Blumenthal. “In many hospitals in the US, allergists have devised protocols to rapidly screen patients with a history of severe allergies before vaccination.” Confusion and mixed messages during the Covid-19 coronavirus pandemic? Imagine that.

Ultimately, Covid-19 vaccine safety is about numbers. Everything in life has its risks, with the possible exception of avocado toast. A pillow could be a deadly weapon. Posting a photo of you eating a hot dog on Instagram could cause harm if someone else has very strong feelings for hot dogs. This does not mean that you avoid all pillows and hot dogs. So far, the risk of serious allergic reactions does not appear to be very high. That does not mean that such reactions should not be followed and reported. However, like Jim Carrey’s character in the movie Dumb and dumb You may not have realized it, just because there is a possibility that something will happen does not mean that it is likely to happen.