New COVID-19 XE Variant Identified: What to Know

More than 600 cases of the new variant have been confirmed in the United Kingdom.

Crowd from above forming a growth graph with lines connecting between them to show how th COVID-19 can expand
Getty Images

A new COVID-19 variant has been identified in the United Kingdom, according to top agencies, but public health experts say it's not currently a cause for concern.

The new variant, known as XE, is technically a hybrid of BA.1, the original Omicron variant, and BA.2, previously known as "stealth" Omicron. The recombinant virus—which means it's a combination of two previously-identified strains—is being closely monitored to determine its transmissibility and severity.

"There are still things that need to be sorted out with this variant, but this is not grounds for panic," Thomas Russo, MD, professor and chief of infectious disease at the University at Buffalo, told

Though more research is needed, here's what's known about the COVID-19 XE variant so far.

What Is the New COVID-19 XE Variant?

According to a recent COVID-19 Weekly Epidemiological Update by the World Health Organization (WHO), the XE variant was first identified in the UK on January 19. Since then, 637 cases have been reported and confirmed in England. However, the U.K. Health Security Agency (UKHSA) said XE only accounts for less than 1% of total sequenced cases.

The XE variant is a recombinant of the previously identified Omicron strains, BA.1 and BA.2. According to the UKHSA, the spike protein of the XE variant—which the SARS-CoV-2 virus uses to latch onto cells—is the same as that of BA.2.

Outside of the genetic makeup of the XE variant, not much else is known about the new COVID-19 strain. Though the WHO shared in its epidemiological update that the XE variant appears to have a community growth rate advantage of about 10% over BA.2, more research needs to be done.

"This particular recombinant, XE, has shown variable growth rate and we cannot yet confirm whether it has a true growth advantage," Susan Hopkins, Chief Medical Advisor for the UKHSA said in a statement. "So far there is not enough evidence to draw conclusions about transmissibility, severity, or vaccine effectiveness."

The New COVID-19 XE Variant Is Not a Surprise

XE isn't the first COVID-19 variant, and it likely won't be the last. "This was an expected recombination event," Amesh A. Adalja, MD, a senior scholar at the Johns Hopkins Center for Health Security, told

The UKHSA explained that recombinant viruses occur when an individual becomes infected with two or more variants at the same time, allowing mixing of the viruses' genetic material.

"Recombinant variants are not an unusual occurrence, particularly when there are several variants in circulation, and several have been identified over the course of the pandemic to date," Dr. Hopkins said in a statement. "As with other kinds of variant, most will die off relatively quickly."

Other COVID-19 Recombinant Variants

In addition to the XE variant, the WHO and UKHSA noted that two other recombinant variants—XD and XF, both Delta and Omicron (BA.1) recombinants—have been identified.

The two other recombinant variants have led to fewer reported cases: Only 38 cases of the XF variant have been identified, and none have been reported since mid-February, the UKHSA said. Meanwhile, 49 cases of the XD variant have been identified in France.

Reduced COVID-19 Testing May Be an Issue

Despite little worry from experts on the XE variant (or the other two variants), the WHO warns that these discoveries are happening at a time when there is "significant reduction in SARS-CoV-2 testing" by countries around the world.

"Data are becoming progressively less representative, less timely, and less robust," the WHO stated in its weekly report on the pandemic. "This inhibits our collective ability to track where the virus is, how it is spreading, and how it is evolving: information and analyses that remain critical to effectively end the acute phase of the pandemic."

In other words, while the WHO and other public health agencies know that Omicron XE is out there, they're not entirely confident that current numbers accurately reflect just how widespread the variant may be.

While more data needs to be collected on the XE variant, experts say there's no evidence of a public health risk as of right now. "This is not a cause for concern," Dr. Adalja said.

The best protection against the XE variant—or any other variant—is vaccination, or previous protection from the virus. "If you were infected with BA.1, BA.2, or vaccinated, you should have immunity against [the XE variant]," Dr. Russo said.

For now, "people should continue to do all the usual things to stay safe," he added. "Make sure you're up to date with your vaccinations and, if there's a lot of COVID in your area and you're at an increased risk of severe disease, wear a mask."

The information in this story is accurate as of press time. However, as the situation surrounding COVID-19 continues to evolve, it's possible that some data have changed since publication. While Health is trying to keep our stories as up-to-date as possible, we also encourage readers to stay informed on news and recommendations for their own communities by using the CDC, WHO, and their local public health department as resources.

Was this page helpful?
Related Articles