A new COVID-19 variant, XFG, has rapidly become the third most common strain in the United States. Nicknamed “Stratus,” the variant accounted for 14% of U.S. cases by late June, according to the Centers for Disease Control and Prevention.
First detected in Southeast Asia in January, XFG registered negligible levels of infection in the U.S. until May. Its prevalence then climbed steadily, from 2% in April to 11% in early June, before reaching 14% in the two-week period ending June 21. This places it behind the NB.1.8.1 (43%) and LP.8.1 (31%) variants. The CDC has noted it now uses longer tracking periods due to reduced reporting from states.
Globally, the World Health Organization also tracked a significant increase in XFG. A June report showed the variant grew from accounting for 7.4% of positive tests worldwide in early May to 22.7% by the end of the month.
XFG is a recombinant variant, combining strains F.7 and LP.8.1.2. According to Subhash Verma, a microbiology and immunology professor at the University of Nevada, Reno, mutations may allow XFG to better evade immune responses. However, its binding behavior suggests it is less contagious than other dominant variants.
Despite its spread, health officials have assessed the variant’s risk as low. In its June report, the WHO evaluated the public health risk from XFG as “low” at a global level and stated that current COVID-19 vaccines are expected to remain effective against severe disease.
“There is currently no clear evidence that XFG causes more severe disease or significantly different symptoms than earlier Omicron variants,” Verma said, adding that there are “no immediate public health concerns associated with this variant.”
While there is no scientific evidence that XFG produces distinct symptoms, hoarseness has been anecdotally associated with the strain in news reports and on social media. The CDC continues to list the following as common symptoms of COVID-19:
* Fever or chills
* Cough
* Shortness of breath or difficulty breathing
* Fatigue
* Muscle or body aches
* Headache
* New loss of taste or smell
* Sore throat
* Congestion or a runny nose
* Nausea or vomiting
The agency advises seeking immediate medical care for emergency warning signs such as trouble breathing, persistent chest pain or pressure, new confusion, an inability to wake or stay awake, or skin, lips, or nail beds that appear pale, gray, or blue.
Source link