Does Omicron Increase COVID-19 Reinfection Risk?

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Verywell Health / Theresa Chiechi

Key Takeaways

  • Preliminary evidence suggests that there is an increased risk of reinfection with the Omicron variant.
  • Cases of COVID-19 reinfection remain relatively rare, and should they occur, they tend to be less severe than the initial infection.
  • Reinfection may be uncommon 90 days after the initial infection, but it's still important to get your vaccine and booster shots.

So you got COVID-19 once. Can you get it again? Unfortunately, you can, and with the emergence of the Omicron variant, many fear that COVID-19 reinfections may become more common.

According to the Centers for Disease Control and Prevention (CDC), COVID-19 reinfections are to be expected based on our knowledge of other coronaviruses. This means that any individual who has recovered from COVID-19 can get infected again.

Although cases of reinfection are generally rare, the virus mutates by nature, and there’s always a chance that new variants may behave differently from what we expect. Variants like Omicron may be able to evade any natural immunity you may have developed from previous COVID-19 variant infections.

We're still learning more about COVID-19 and it’s not yet entirely clear how well previous infections protect against Omicron. Here's what we know so far.

Is Reinfection More Likely With Omicron?

According to the World Health Organization, it's possible that there is an increased risk of reinfection with the Omicron variant.

“Early studies from across the world suggest that the Omicron variant is distinct enough from the original ancestral SARS-CoV-2—[the virus that causes COVID-19]—strain to increase the probability of reinfections,” Julio Silva, MD/PhD candidate, and student researcher in the Department of Immunobiology at the Yale School of Medicine, told Verywell. “The quantity of this here in the United States is an active point of investigation.”

A preprint study posted last December on medRxiv suggests that the Omicron variant may be able to evade natural immunity from a previous COVID-19 infection. Another preprint study posted earlier this month found that a previous infection protects against symptomatic reinfection with the Alpha, Beta, or Delta variants by about 90%, but only 30% for the Omicron variant. These studies have yet to be peer-reviewed, so they can't yet be used to guide clinical practice.

The probability of reinfection may depend on many factors, Silva said, such as:

  • Your baseline immune system
  • Time since the last infection
  • Time since COVID-19 vaccination
  • The COVID-19 strain that you were originally infected with
  • The COVID-19 strain in circulation

“Reinfections tend to be less severe than the first infection,” Silva added. “This is because your immune system has at least some memory of the previous infection and can more quickly assemble the immune response to fight it off by antibody production and cellular memory.”

A comparative study published in The New England Journal of Medicine found that reinfections had a 90% lower risk of hospitalization and death than primary infections. Out of the 1304 cases of reinfection the researchers studied, there were four severe cases and no critical or fatal reinfections.

“Reinfection remains relatively rare,” Daniel Bachmann, MD, emergency medicine physician at The Ohio State University Wexner Medical Center, told Verywell. “Accordingly, it is possible that mild or asymptomatic cases are not being reported and thus our understanding is somewhat incomplete.”

Although cases of reinfection are rare, it's important to continue taking appropriate precautions such as mask-wearing, physical distancing, and vaccination to reduce the transmission of the virus.

What This Means For You

It is uncommon to get reinfected for about 90 days after your initial COVID-19 infection. However, to maximize your protection against the virus and reduce the risk of reinfection, you should get vaccinated or get your booster shot as soon as you are eligible for it.

Can You Get Reinfected Immediately?

According to the CDC, reinfection is uncommon during those 90 days after your initial COVID-19 infection. You’re unlikely to get reinfected for some time because you have probably developed at least some level of natural immunity. Some studies show immunity that lasts for five to 12 months.

When you have COVID-19, the body produces antibodies against the virus, which protects against reinfection. If your body’s immune system is compromised or diminished, it may not produce many or any antibodies in the first place. You are at risk for another infection as the level of antibodies decreases, Bachmann said.

“As with vaccination, reinfections tend to increase with increasing time since your first infection,” Silva said. “That is, the more time that has passed since the previous infection, the more likely it is to have reinfection. However, these occurrences are still very rare.”

A CDC study shows that unvaccinated individuals are significantly more likely to get reinfected by COVID-19, which emphasizes the importance of getting vaccinated. If you had a breakthrough infection, experts still recommend getting the booster shot to avoid reinfection even further.

“There is some limited data that shows vaccination after infection reduces risk of reinfection,” Bachmann said. A study published in Cell concluded that two doses of mRNA COVID-19 vaccines are not enough to neutralize the Omicron variant; therefore, a booster dose is needed. We have yet to know what this means for reinfection.

Overall, getting a booster shot helps you maximize your immunity against COVID-19, and it's best to have all the protection you can get.

An initial COVID-19 infection likely provides a strong local memory immune response in the body, and a booster dose may give it an additional memory boost to prolong the time before the antibody levels decrease, Silva noted.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. World Health Organization. Statement – Update on COVID-19:Omicron is gaining ground: Protect, prevent, prepare.

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  6. Centers for Disease Control and Prevention. Answering patients’ questions about COVID-19 vaccine and vaccination.

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  8. Cavanaugh AM, Spicer KB, Thoroughman D, et al. Reduced risk of reinfection with SARS-CoV-2 after COVID-19 vaccination — Kentucky, May–June 2021. MMWR Morb Mortal Wkly Rep. 2021;70:1081-1083. doi:10.15585/mmwr.mm7032e1

  9. Garcia-Beltran WF, St. Denis KJ, Hoelzemer A, et al. mRNA-based COVID-19 vaccine boosters induce neutralizing immunity against SARS-CoV-2 Omicron variant. Cell. Published online December 23, 2021. doi:10.1016/j.cell.2021.12.033

By Carla Delgado
Carla M. Delgado is a health and culture writer based in the Philippines.