New COVID Variant XFG Sparks Health Alerts

A new COVID-19 variant, XFG, also known as 'American COVID' or 'Stratus,' is now circulating as a rise in coronavirus activity is reported. The UK Health Security Agency noted a significant increase in positive test results and hospital admissions in September. Similar trends have been observed across Europe and the United States.

XFG is a hybrid of earlier variants LF.7 and LP.8.1.2, with its earliest known sample dating to January 2025. The World Health Organization began monitoring it in June 2025 as it spread globally. Related lineages have been predominant in U.S. wastewater surveillance.

While XFG shares common COVID-19 symptoms like cough and fever, a hoarse voice has been noted as a potentially distinguishing symptom. However, definitive identification relies on genetic sequencing rather than symptoms alone. The WHO has assessed the variant's global public-health risk as low, with no indication of causing more severe illness or deaths.

Approved COVID-19 vaccines are expected to remain effective against XFG. Public health agencies suggest that factors like colder weather, increased indoor gatherings, and waning immunity from previous infections or vaccinations may contribute to the rise in cases. The 'American COVID' nickname reportedly stems from where the strain was first sequenced, not necessarily its origin.