COVID vaccine side effects: Why some people get them and others don’t

Some people have experienced mild side effects after getting vaccinated for COVID-19, while others have not.

All three of the vaccines approved for use in the United States — Moderna, Pfizer and Johnson & Johnson — come with potential side effects like a sore arm, fatigue, fever, muscle aches, headaches and chills.

Experts said with the two-dose vaccines, the side effects usually happen after the second dose.

Roughly 40% of the population will have side effects, but the question is why some people and not others?

“Two people who look the same on paper, who get a COVID-19 infection, one can end up on a ventilator severely ill, the other can be home for a couple of days with mild symptoms. The same is true for vaccines. Each person’s immune system works uniquely,” said Dr. Joseph Khabbaza of the Cleveland Clinic.

In clinical trials, those 55 years old and younger experienced more side effects. Doctors said that is the case now as more and more people are getting the vaccine.

“Older people also have older immune systems. The older population typically doesn’t have quite as much of a reaction if you will, but they still have the protection. I can’t overstate that point,” said Dr. Amy Ray with the MetroHealth System.

Side effects often appear after the second shot of the two-dose vaccine. With Johnson & Johnson, which is only one dose, side effects can start a couple of hours after the injection.

Doctors said the side effects are temporary, lasting only a few hours and the benefits outweigh the risk of not getting a COVID-19 vaccination.

“It is a form of playing with fire to choose not to get vaccinated in the middle of a deadly pandemic,” said Khabbaza.

Doctors also said do not take any pain reliever before your vaccination to ward off the side effects, as doing so could lower the immune response.

By Tracy Carloss, WEWS.