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By now, millions of Americans have had COVID-19, whether they know it or not. In fact, a growing number of people are now getting the virus a second time. If you've had the coronavirus more than once—or you know someone who has—you might wonder what's happening.

How do people get COVID-19 twice?

Having COVID-19 gives most people some protection from repeat infections. Getting fully vaccinated provides a safeguard too. According to the Centers for Disease Control and Prevention (CDC), most people have a low risk of reinfection for at least six months after becoming fully vaccinated or getting sick with the virus.

Why doesn't protection last longer? There are two main reasons:

New variants. When you become infected with a virus like the one that causes COVID-19, your immune system learns how to defend your body from that infection. But, like all viruses, the coronavirus that causes COVID-19 changes as it spreads. New variants and subvariants may be different enough to get past your defenses.

Waning immunity. When you get sick with COVID-19—or when you get a dose of the vaccine—your immune system produces antibodies to fight off COVID-19. But the levels of those antibodies decrease over time, CDC reports—and that's especially true for older adults and people whose immune system is compromised.

As new variants spread and immunity fades, people are more likely to get COVID-19 again. And that's a problem: Research indicates that reinfection may increase the risk of developing chronic health conditions.

How can I avoid getting COVID-19 again?

The pandemic isn't over, but you can protect yourself with vaccines and smart decisions.

The best way to avoid reinfection is to make sure you're up-to-date on COVID-19 vaccines. If you've already been vaccinated, it may be time for a bivalent booster.

The updated boosters help protect against the original virus as well as two Omicron variants. They can provide added protection even if you've already had COVID-19.

If you haven't been vaccinated yet, you have options. Both mRNA and more traditional vaccines are available. Your doctor can help you decide on the best choice for you.

Your lifestyle also plays a role in the risk of reinfection. If you interact with the public or live in an area with a high infection rate, consider extra precautions. That might include wearing a mask or asking guests to test for COVID-19 before large gatherings.

You can learn more about how to protect yourself from COVID-19 in our Coronavirus health topic center.

Reviewed 4/19/2023

Sources

• American Medical Association. "What Doctors Wish Patients Knew About COVID-19 Reinfection." https://www.ama-assn.org/delivering-care/public-health/what-doctors-wish-patients-knew-about-covid-19-reinfection.
• Centers for Disease Control and Prevention. "Science Brief: SARS-CoV-2 Infection-induced and Vaccine-induced Immunity." https://www.cdc.gov/coronavirus/2019-ncov/science/science-briefs/vaccine-induced-immunity.html.
• Centers for Disease Control and Prevention. "Stay Up to Date with COVID-19 Vaccines Including Boosters." https://www.cdc.gov/coronavirus/2019-ncov/vaccines/stay-up-to-date.html.