Updated: 08/31/2023

When COVID-19 was a new virus, people assumed that they’d only get it once. Now, more than three years later, some people have gotten it several times.

“COVID-19 is a virus that may infect people over and over,” says chief physician executive Danial Varga, M.D. “It shares similarities with the flu, not chicken pox, which people only get once.”

Even if you’ve had COVID-19 in the past, you may be at risk again. Read on to find out why, plus how to lower your risk.

Why You May Be at Risk of COVID Reinfection

How many times have you had a cold or the flu in your lifetime? Probably more times than you can remember.

The COVID-19 virus has qualities in common with the common cold and the flu. All of these viruses may mutate, so you catch a slightly different virus.

“This is why flu vaccines may change every flu season,” Dr. Varga says. “Every year, the vaccine targets flu viruses that are expected to spread widely. ”

These factors may increase the risk of COVID-19 reinfection:

• COVID-19 variants. When COVID-19 mutates, different variants are created, like Delta and Omicron. Having had the Delta variant may not have protected you from Omicron.
  
  “Some people have a false sense of security after getting COVID-19, thinking they can’t get reinfected,” Dr. Varga says. “In truth, anyone may test positive for COVID-19 any number of times.”
  
  
• Changing levels of antibodies. When you have COVID-19, antibodies may remain in your system for weeks or months. These antibodies may offer you some temporary protection from reinfection.
  
  After weeks or months, the level of COVID-19 antibodies in your system may decrease. Fewer antibodies don’t offer as much protection, so you may get sick again.
  
  
• The passage of time after vaccination. Getting vaccinated against COVID-19 is another way to build up antibodies. But over time, even those antibody levels wane, making you more susceptible to illness.
  
  Because COVID-19 is relatively new, researchers continue to learn about it. It’s unknown exactly how long COVID-19 antibodies offer protection from reinfection.
  
  Different studies have found that antibodies are protective for different lengths of time. Are they effective for several months or just a few weeks? More research is needed.
  
  Some guidelines suggest that COVID-19 antibodies may offer protection for three months. After that time frame, reinfection may be more likely.

In many cases, reinfection after vaccination or COVID-19 infection results in milder illness. However, this isn’t guaranteed.

“Doctors recommend that vaccinated people get COVID-19 boosters to elevate their antibody levels,” Dr. Varga says. “Vaccinated people are more likely to have mild illness if they’re reinfected.”

How to Lower Your Risk of COVID Reinfection

Repeat COVID-19 cases may be milder, but it’s best to avoid illness altogether. There are several ways to reduce your risk of reinfection:

• Get vaccinated, and stay up-to-date on booster shots. Increasing your exposure to COVID-19 antibodies may offer protection.
• Wear a mask in crowded, enclosed spaces if COVID-19 transmission rates are high. Be sure that your high-quality mask covers your nose and mouth. 
• Spend time outdoors when socializing, or open windows to improve ventilation while indoors. Using fans helps to improve air flow, so that virus particles don’t linger.
• Stay away from sick people, and get tested for COVID-19 if you’re exposed. 

If you’re reinfected with COVID-19, stay home to reduce the spread. If you’re COVID-negative, stay home to reduce the spread of colds or flu.

Next Steps & Resources:

• Meet our source: Daniel Varga, M.D.
• To make an appointment with a doctor near you, call 800-822-8905 or visit our website. 

The material provided through HealthU is intended to be used as general information only and should not replace the advice of your physician. Always consult your physician for individual care.