Actions

New study finds COVID-19 survivors may only need 1 vaccine shot

The new study found that people who recovered from COVID-19 - even very mild cases of it, up to eight months ago - likely only need one dose of the vaccine, instead of the required two.
Vaccine shortages have plagued much of the world, including the U.S. Now, a new study finds not everyone may need two shots of the approved vaccines.
Researchers at the University of Maryland School of Medicine examined health care workers who previously had COVID-19. They already had antibodies from having fought off the virus. After just their first vaccine shot, their bodies showed levels of antibodies that would normally be seen after getting two required doses of the vaccine.
Posted
and last updated

WASHINGTON, D.C. — By now, it’s a familiar situation at vaccine distribution sites: there's a lack of COVID-19 vaccine doses, even for people with confirmed appointments to get one.

"There's a shortage and we have no vaccinations to give out here today,” a worker at one southern California site told those in line.

Those who waited for their shot left disappointed.

"I think it's horrible,” said Beverly Kee. “I think it's really horrible."

Part of the issue is that the currently approved COVID-19 vaccines all require two separate shots. Now, though, a new study finds two shots may not be needed for everyone.

“We thought, ‘well, this is a unique opportunity to do an additional study,’” said Dr. Anthony Harris, an infectious disease physician with the University of Maryland School of Medicine.

After doing COVID-19 antibody testing on 10,000 health care workers, he and his colleagues decided to take a closer look at nearly 60 health care workers who previously had the virus and then got vaccinated.

“We hypothesized that the people that had had COVID-19 before likely would behave differently, and that's in essence what we found,” he said.

The finding: health care workers who had COVID-19 before already had antibodies from having fought off the virus. After just their first vaccine shot, their bodies showed levels of antibodies normally seen after getting two doses.

“When they got the first dose of vaccine, they've got this massive antibody response, with very high levels, in response to the first dose,” Dr. Harris said.

That means people who recovered from COVID-19, even very mild cases of it, up to eight months ago, likely only need one dose of the vaccine, instead of two, Dr. Harris said. That could help expand the amount of vaccines available.

Their study isn’t alone. Others found similar results.

“With four studies coming out one in one week, it led governments to review the data quickly,” Dr. Harris said. “So, as an example, late last week, France announced that anyone who had had coronavirus previously, they would go lower on the priority list and, when they were vaccinated, they would only receive one dose.”

The study is currently getting looked at by the Centers for Disease Control and Prevention (CDC) and peer-reviewed by other scientists. For now, though, two shots remain the standard for everyone in the U.S. with the currently approved vaccines.

However, Dr. Harris says the new study could help governments here and around the world better manage the limited vaccine supply available right now, which might help slow down any mutations of the virus.

“The faster we can get people vaccinated, the less of a risk these variant strains are,” Dr. Harris said.

You can take a closer look at the study results by clicking here.

Coronavirus Resources and Information

Johns Hopkins global coronavirus tracker