Can The COVID-19 Vaccine Give You The Virus?

What are your questions about the coronavirus vaccine?

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Monica called ideastream to ask why she started getting COVID-19 symptoms after receiving the vaccine. Her symptoms lasted 6-7 days and included loss of taste and smell, runny nose, and teary eyes.

There’s no way the vaccine caused the symptoms Monica is experiencing, said Dr. Keith Armitage, an infectious disease specialist at University Hospitals.

“You absolutely cannot get the virus from the vaccine,” he said. “None of the vaccines contain the virus.”

The vaccines contain a small fragment of genetic material that allows the body to produce an immune response, but they don’t contain the rest of the genes of the virus, Armitage said.

“None of the vaccines contain anything close to a live coronavirus,” he said.

Dr. David Margolius, division director of internal medicine at MetroHealth, agrees that there’s no way Monica caught COVID-19 from the vaccine.

“What’s inside the vaccine are instructions to make a tiny, tiny part of the virus, which disintegrates after your immune system takes care of it,” Margolius said. 

The vaccine doesn’t have a live virus in it that would cause those problems, he said.

What likely happened is that Monica was exposed to the virus before she was fully protected.

With the Pfizer and Moderna vaccines, people can become infected up to twelve days after receiving the vaccine, Armitage said.

“Around day 12 the protection really starts to kick in and after day 12 of the first shot, the risk of hospitalizations and death goes way down, as does the risk of infection,” he said.

The Johnson & Johnson vaccine is different though, Armitage said.

In data presented to the FDA, the patient’s antibody levels increased for 56 days after receiving the Johnson & Johnson shot, he said.

“I think it’s just that the immune system needs its chance to spread the word," Margolius said. 

That means that a person will become more protected from COVID-19 overtime after receiving that brand of vaccine, Armitage said. 

There is some protection after the first two weeks of receiving the Johnson & Johnson vaccine, but the protection is much better after day 28.

Other listeners had similar questions about finding out they had COVID after getting the vaccine.

“Do I need to reschedule another vaccine shot?” Marcelo asked. “Recently I was diagnosed with COVID-19 just three days after I received the single-shot Johnson & Johnson vaccine.”

No, he doesn’t need to get another shot, Armitage said.

Marcelo might have also been exposed to COVID-19 when he wasn’t fully protected, since he tested positive three days after, but it’s also possible he had a previous infection, Armitage said.

“If he contracted COVID before getting the shot, you can still test positive sometimes for several weeks because the test doesn’t mean you’re actively infected. It means you’ve probably had infection,” he said.

“In other words, the molecular test for the virus stays positive in people even when they no longer have an infection.”

Mitzie from Hartsville has been experiencing fatigue since receiving the first shot. She had COVID in October and wondered if the fatigue was from the shot.

It’s possible for people to have fever, chills, and fatigue after the shot, but it goes away after 24-48 hours, Margolius said.

So there’s no way Mitzie’s fatigue is caused by the shot, he said.

Dr. Armitage agreed, but he said there are early reports of people who have had COVID having a worse response to the first shot than the second.

“People who have had COVID, their immune system is primed,” he said.

That means the person has already started to develop an immune response to the virus, but it’s still important they get the vaccine, Armitage said.

The vaccine gives much better immunity than natural protection, he said.

It wouldn’t last more than 48 hours, so Mitzie’s long-term fatigue is likely not caused by the vaccine, he said.