Health officials recommend preparing for side effects from COVID-19 vaccines, ‘small price to pay’ for immunity

MADISON, Wis. – Side effects mean the COVID-19 vaccines are working, but some will experience a level of symptoms they haven’t with vaccines in the past.

“There really is no secret rhyme or reason with people that experience them,” said Jennifer Bothum, a registered nurse at SSM Health, adding that your reaction to a past flu shot doesn’t predict how you’ll react to a COVID-19 vaccine.

Alex Van Rossum of the Madison area went into her Johnson & Johnson vaccine appointment this week with the expectation of some side effects, but also hope.

“I was excited,” Van Rossum said. “Both my grandparents are vaccinated. Now that I am vaccinated in two weeks, I can see them again.”

About 12 hours later, side effects were hitting their peak.

“I started to get really, really achy,” she said. “I got a headache and then I started getting chills and developed a fever.”

‘Their job is to produce those effects’: Inflammation brings symptoms

“Those are totally normal and expected things,” said Dr. William Hartman, head of the AstraZeneca vaccine trials at UW Health.

A vaccine’s reactogenecity is how much it produces expected adverse reactions from the body’s immune response, such as fever and sore arm at the shot site.

“These are very reactogenic vaccines,” Hartman said. “Their job is to produce those effects so your body can remember when it sees this virus, to go after it.”

Harman explains that your body building defense causes inflammation, leading to symptoms such as fever, headache and body aches.

Side effects may be stronger in people who have already had COVID or after someone’s second shot because their bodies are already “primed” with an immune response. Young people may get more intense symptoms, as well.

“Younger folks with more robust immune systems have a more robust response to this,” Bothun said.

Bothun said the most common side effect is a sore or stiff arm, shown by the FDA to be the most common symptom among all three approved COVID-19 vaccines, as well. As the regional manager of employee health, she said only about 10-15% of SSM Health employees had symptoms severe enough that would lead someone to call-in to work.

‘We hear about them more often’

In general, Bothun and Hartman said the COVID-19 vaccines are generating more reports of side effects than others such as a flu shot.

“We hear about them more often,” Hartman said. “Perhaps people are more aware of it because this is a new vaccine and it’s been in the news so much that they’re just more aware of what’s happening to their body once they get the vaccine. It’s hard to say.”

“I don’t know if it’s necessarily worse or we’re paying more attention to it,” Bothun said.

Hartman said he’s not seeing “a tremendous amount of difference” in side effects reported from the three approved vaccines, adding that early reports showed those who got the Moderna vaccine were slightly more likely to experience side effects than the Pfizer vaccine, and the Johnson & Johnson vaccine is still so new it’s hard to say how much side effects between the three differ.

In Johnson & Johnson’s clinical trial, more than 60% of younger patients had systemic reactions compared to about 45% of patients over age 60.

Pfizer and Moderna’s studies show similar numbers, but not as large of a difference. The amount of reactions increase with the second shot.

‘The golden ticket’: Not everyone has side effects

Hartman said those without side effects shouldn’t worry.

“That doesn’t mean your body’s not doing what it’s supposed to,” he said. “It just means you have kind of the golden ticket.”

For those who do experience side effects, they’re usually short-lived, though Bothun recommends seeking medical attention if they last past 48 hours. She also advises drinking plenty of water, being well-rested on the day of the shot and allowing some time to take it easy in case side effects do arise.

Fevers can also be treated with Tylenol or Ibuprofen after the shot, though those drugs should be avoided before the vaccination.

“A couple days of not feeling well is a small price to pay for some immunity over a potentially devastating disease,” Bothun said.

That immunity is the best side effect of them all.

“I’ll deal with some weird side effects now to ensure a global pandemic can get under control,” Van Rossum said.