COVID XFG variant (The Stratus): Symptoms, Global Spread, and Impact in Late 2025

The Stratus variant, scientifically designated as XFG, is a sublineage of the Omicron family of SARS-CoV-2 (the virus causing COVID-19). It was first detected in Southeast Asia in January 2025 and classified by the World Health Organization (WHO) as a Variant Under Monitoring (VUM) on June 25, 2025. XFG is characterized by specific genetic mutations, including JF1 + S:T22N, S:S31P, S:R190S, S:R346T, S:K444R, S:V445R, S:F456L, S:N487D, S:Q493E, and S:T572I, which contribute to its increased transmissibility compared to some prior Omicron subvariants. It has a estimated daily growth advantage of about 6% over other circulating strains. The WHO's initial risk evaluation considers it a low public health risk overall, with no clear evidence of increased severity or immune evasion beyond existing Omicron variants. Symptoms Symptoms of the Stratus (XFG) variant are largely consistent with those of previous Omicron subvariants, though anecdotal reports and social media discussions highligh...