New COVID-19 XEC Variant Spreading Rapidly in Europe and Canada: What We Know

A New COVID-19 Variant: XEC Spreading in Europe and Canada

As COVID-19 activity remains high, a new variant called XEC has emerged and is spreading rapidly in Europe and other parts of the world. Only a handful of cases have been detected in the U.S. so far, but some experts are projecting that XEC could be on track to become the dominant strain this fall.

The Rise of XEC

The SARS-CoV-2 virus, which causes COVID, is continuing to mutate, giving rise to new, highly contagious variants. The latest one to gain interest and make headlines is the recombinant variant, XEC, which has been found in at least half of U.S. states. XEC is a combination of two other SARS-CoV-2 variants known as KP.3.3 and KS.1.1. It formed when the two variants infected the same organism – such as an animal or person – simultaneously, allowing them to share genetic material.

XEC's Transmission and Prevalence

XEC was first identified in August amongst COVID-19 samples collected in Berlin two months earlier. The earliest cases of the variant occurred in Italy in May. However, these samples weren’t uploaded to an international database that tracks SARS-CoV-2 variants, called the Global Initiative on Sharing All Influenza Data (GSAID) until September.

Data from GSAID indicates that more than 600 cases of XEC have been reported across 27 countries, including the UK, Germany, Canada and the US. However, “not all countries consistently report data to GSAID, so the XEC variant is likely to be present in more countries”, says Bhanu Bhatnagar at the World Health Organisation (WHO) Regional Office for Europe.

The variant is prevalent in Europe, where at least 13 countries have detected it, says Bhatnagar. So far, XEC constitutes about 8 per cent of all sequenced and reported samples from the continent this month, according to data from GSAID. By comparison, it made up about 4 per cent of samples in August. The most commonly sequenced variant in Europe is still KP.3.1.1 – also in the omicron family – at 48 per cent of all samples, says Bhatnagar.

XEC is most widespread in France, comprising roughly 21 per cent of sequenced COVID-19 samples. It is also gaining traction in Germany and the UK, where it represents 15 per cent and 8 per cent of sequenced samples, respectively, says Francois Balloux at the University College London.

XEC in Canada

XEC was first detected in Canada at the end of July and in Ontario in early August, according to Scripps Research. But the most dominant strain in the province is still KP. 3.1.1, an Omicron variant.

The most recent data, available for the week of Aug. 25-31, shows KP. 3.1.1 made up 50.5 per cent of cases, a number that was forecasted to rise to 60.2 per cent by Sept. 18.

Likewise, the most recent national numbers also show KP. 3.1.1 as the most dominant strain. Health Canada estimated it would make up 67.5 per cent of cases nationally by Sept. 8.

But variants spread quickly and if XEC is already starting to replace a more dominant variant in one area, “it’s likely that that will take over as the more dominant sublineage,” Bogoch said.

Symptoms and Severity

The XEC variant likely has the same symptoms as existing COVID-19 variants, with the potential for some subtle differences, Bogoch said. According to Health Canada, typical COVID-19 symptoms include:

Fever
Cough
Sore throat
Shortness of breath
Muscle aches
Headache
Loss of taste or smell
Fatigue
Nausea and vomiting
Diarrhea

The severity of XEC — and how to slow its transmission — is likely the same, too, according to Bogoch. It does not appear to be more dangerous or produce more severe disease than past COVID-19 variants, says Schaffner. The WHO hasn’t designated it as a variant of concern, either. That is because it shares many of the same characteristics as other omicron subvariants, like causing more mild illness than earlier strains, says Schaffner.

The Impact on Vaccines

The good news is that current COVID-19 vaccines are expected to protect against XEC, says Schaffner. This is because updated versions target omicron subvariants. The CDC recommends everyone 6 months or older receive an updated COVID-19 booster if they haven’t done so this year. In the UK, updated vaccines are available to people 75 years and older, and those who live in senior care facilities or have a weakened immune system.

While the new vaccines were developed before XEC emerged, the primary goal of the vaccine is to protect those who are most vulnerable by reducing the risk of hospitalization and death. XEC doesn’t change that.

“Regardless of the vaccine, it will still do a very good job in reducing the risk of severe manifestations of the virus,” Bogoch said.

Public Health Advice

The public health advice will likely remain the same, according to Bogoch. Wash your hands often, cover your mouth when you cough or sneeze and wear a mask in indoor public settings, the province advises. And if you’re sick, stay home until your symptoms have been improving for at least 24 hours.

If you’re behind on vaccinations, the province previously recommended waiting until the fall to get your next dose. That will ensure maximum protection when virus circulation is expected to be at its highest.

“We know what the vaccines do, we know what masks do, we know what improving air quality does,” Bogoch said. “We’ve been through this now, coming up on five years, and I don’t think there’s going to be any surprises.”

What's Next?

It is too early to say whether XEC is more transmissible than other variants, says James Fielding at the WHO. Given that it has gained a foothold amongst other circulating variants, however, it may have an advantage that makes it spread more easily. For instance, a preliminary analysis from Mike Honey, a data specialist in Australia, suggests that XEC will become the dominant variant in Europe and the UK in October. He predicts the same will occur in the US and Canada later that month or in November.

“How widely [spread] this particular strain will become, I think we just have to wait and see,” says Schaffner.

“We’ll know in November.”

XEC: Same Old, Same Old?

Ultimately, Schaffner says there is no reason to panic about XEC. “The virus is just getting going, but it appears to be following the same pattern [as past ones]” he says. “My response is: same old, same old.”

While the world is now on high alert for any new COVID-19 variants, the overall message from public health experts is one of cautious optimism. While XEC is certainly worth monitoring, the tools and strategies we have in place to protect ourselves and our communities remain effective.