rantoul covid

OSF nurse practitioner Glenett Barrett explains possible side effects of the coroanvirus vaccine to Bruce Hopper of Champaign on Friday at OSF's vaccine clinic in the Rantoul Park District Youth Center.

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URBANA — If you’re worried about getting hit with dreadful side effects from your second COVID-19 vaccine shot, a local doctor said effects after those second doses have largely been on the mild side.

For most people who experience second-dose side effects — and not everyone does — the symptoms can usually be knocked back with a dose of Extra Strength Tylenol and should be gone within a day, according to Dr. Michael Smith, a Carle Foundation Hospital emergency medicine physician.

“The side effects we’re seeing are fairly common, but also fairly mild,” he said.

Smith cited a British study that found a small percentage of people get flu-like symptoms after the first vaccine dose.

And closer to half of people getting the second dose experience such effects as a low-grade fever, chills, mild headache and sometimes a cough, “in general, symptoms that feel like you’re coming down with something,” Smith said.

That was, in fact, his own experience. About six hours after his second shot, he said, he began experiencing some mild side effects. But they went away after he took a single dose of Extra Strength Tylenol.

That’s not to say that some people won’t feel under the weather enough after the second vaccine dose to want to take a day off afterward — but rarely does anyone feel ill enough to seek emergency room care, according to Smith.

Are there any differences in the responses to the Pfizer/BioNTech vaccine and the Moderna vaccine? Smith said no matter which one you’re getting, they both work the same way.

Both vaccines use messenger RNA that teaches cells how to create a harmless protein that will trigger an immune response to protect against the real virus if it enters the body, according to the Centers for Disease Control and Prevention.

A single dose of the vaccine creates a 55-60 percent immune response, while two weeks after the second dose, the immune response grows to 95 percent, Smith said.

The difference with the second shot is that your body has already been exposed to the foreign protein and recognizes it, he said.

“The second time you get the vaccine, your body is recognizing I’ve had this before and I’m going to fight it,” he said.

Those who don’t experience side effects shouldn’t be concerned that the vaccine isn’t working, according to Smith. They’re still getting just as robust an immune response.

All that said, Smith said there’s a bell curve of effects after the vaccine, and while more serious side effects are uncommon, anyone still feeling ill 24 hours after receiving a COVID-19 vaccine should see their doctors.

Getting that second dose is very important, Smith said.

Only about 10 percent of the local community has had COVID-19, which means most people are still vulnerable to getting infected, he said.

Think of it this way: The first dose produces an immune response that is moderately effective, Smith said, and the second dose produces a response that is highly effective.

More to know from Smith:

  • It’s possible that those feeling more ill after receiving the vaccine may be sick as a result of something else. Remember, the COVID-19 vaccine doesn’t protect against anything else but COVID-19.

If you’re younger and it’s possible for you to schedule your vaccination before any scheduled days off from work, that’s not a bad idea in the event you won’t feel so great the day after. But if you’re over 40, the most important thing is to get your vaccine on the first day it’s available to you.

  • If you’re concerned about the possibility of a severe allergic reaction to the vaccine, Smith said the chances for that are one in a million.

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