Does Natural Immunity to COVID-19 Offer Better Protection Than Getting the Vaccine?

Some people who have already recovered from COVID-19 are hesitant to get the vaccine, but the Centers for Disease Control and Prevention (CDC) is urging everyone to be vaccinated because the shot provides better protection than natural immunity.

Recovering from COVID-19 is believed to offer some protection against the virus, but it's unclear how long that protection lasts and it's possible to get COVID-19 more than once. However, the CDC recently found the chances of a person re-contracting COVID-19 is significantly less if they get vaccinated.

"This study shows you are twice as likely to get infected again if you are unvaccinated," Dr. Rochelle Walensky, the director of the CDC, said in a statement.

In a study of hundreds of Kentucky residents who recovered from COVID-19 through June, the CDC found those who were unvaccinated were 2.34 times more likely to be reinfected. It showed the vaccine provides additional protection and indicates COVID-19 vaccines "offer better protection than natural immunity alone," according to the CDC.

One of the biggest problems with relying on natural immunity is that it's unclear how long that protection lasts and the timeline may vary based on the person. Sabra Klein, a virologist at Johns Hopkins University who studies the immune system, said vaccines provide better immunity than natural infection largely because of how they target the virus.

covid-19 vaccine natural immunity
A recent study from the Centers for Disease Control and Prevention found those who already had COVID-19 and got vaccinated were much better protected against the virus than those who were unvaccinated. A nurse prepares COVID-19 vaccines at a baseball game on August 5 in Springfield, Missouri. Spencer Platt/Getty Images

Instead of going after different parts of the virus called antigens, as the immune system does naturally, she said the Pfizer and Moderna vaccines only target the spike protein, which is vital for invading cells. Getting vaccinated after having COVID gives someone a "strong, lasting immunity boost," according to Klein.

Senator Rand Paul has resisted calls for everyone to get vaccinated because he already recovered from the virus. Paul tested positive early last year, the first member of Congress to be knowingly infected, and has said he'll rely on his natural immunity for protection unless there's evidence people who already were infected are "dying in large numbers" or becoming seriously ill.

A recent Axios-Ipsos poll found 25 percent of people who think they may have had the virus are not likely to get vaccinated. It's unclear why these people were reluctant to get vaccinated, as only 15 percent of people who actually tested positive said they weren't likely to get vaccinated.

Herd immunity is critical for ending the pandemic and officials have warned that people failing to get vaccinated may exacerbate the health crisis. About 30 percent of American adults have yet to be vaccinated against COVID-19 and the Delta variant is fueling spikes in cases across the country. The bulk of the danger is posed to unvaccinated individuals, who account for the majority of hospitalizations, and a recent study found vaccines will provide more protection against variants than natural immunity.

Acquired immunity, which happens after a person recovers from COVID-19, may provide different levels of protection to emerging variants to different people, according to the National Institutes of Health (NIH). In studying how natural immunity compares to vaccine-induced immunity, Dr. Francis Collins, director of the NIH, said a study found antibodies acquired from the vaccine may target variants more potently.

This may be because of differences in the antibodies that are produced after getting vaccinated or that natural infection only exposes the body to the virus found in the respiratory tract, whereas a vaccine is delivered to muscle, according to Collins.