Just as COVID Levels Start to Dip, a New Variant Emerges

Sept. 19, 2024 — A new COVID-19 variant called XEC is on the rise, and it has experts who track variants on alert.

Each time a new variant makes a grand entrance onto tracker lists, health officials take notice because it may mean there’s an important change in behavior of SARS-CoV-2, the virus that causes COVID.

Countries reporting rising detections of XEC include Germany, the United Kingdom, and the Netherlands, Australian data scientist Mike Honey posted on the platform X this past week.

XEC’s “characteristic mutations” have been detected in at least 25 states, CBS News reported, with New Jersey, California, and Virginia labs reporting 10 or more cases each. New Jersey detections at least in part stem from the CDC’s testing program for international travelers at Newark Liberty International Airport.

Still, XEC hasn’t gained enough traction in Europe, the US, or any other part of the world for it to be listed as a stand-alone variant on official watch lists maintained by the CDC, European Union, or World Health Organization.

However, Eric Topol, MD, executive vice president of Scripps Research and editor-at-large for Medscape, WebMD’s sister site for medical professionals, believes XEC is the next variant “to get legs.”

The rate at which a new variant takes the stage doesn’t always predict how severe it will be. Around this time last year, health officials sounded alarms about another Omicron variant called BA.2.86, dubbed Pirola, that ultimately didn’t make major waves.

“CDC is not aware of any specific symptoms associated with XEC or any other co-circulating SARS-CoV-2 lineage,” a CDC spokesperson said in a statement to CBS News.

The current dominant variant in the US is called KP.3.1.1, accounting for an estimated 53% of US COVID cases. Its parent lineages are KP.2 and KP.3, and all of these belong to the Omicron family. The SARS-CoV-2 virus mutates over time, and scientists use the names and labels to identify groups of viral variants based on their similarities and on which strains a mutated descendant came from.

KP.3.1.1 has been the predominant COVID variant since early August, when it topped the list with 19%, just barely outpacing its parent KP.3. As the nation heads into respiratory illness season, when flu and RSV also typically rise, the CDC said in its 2024-2025 Respiratory Disease Season Outlook publication that officials don’t expect any unusual severe impacts from the three big viruses.

“CDC expects the upcoming fall and winter respiratory disease season will likely have a similar or lower number of combined peak hospitalizations due to COVID-19, influenza, and RSV compared to last season,” the report stated.

COVID levels in the US remain high, according to wastewater detections, which is a retreat from the CDC’s label of “very high” earlier in the summer. About 15% of COVID tests reported to the CDC are positive, and that rate has been trending downward, as have been COVID-related emergency room visits and hospitalizations.

SOURCES:

CDC: “COVID Data Tracker,” “2024-2025 Respiratory Disease Season Outlook.”

CBS News: “New COVID Variant XEC Now in Half of States. Here’s What to Know.”

X: @Mike_Honey_, September 14, 2024.