Overview

• UKHSA reports XFG (Stratus) as the leading lineage in recent UK sequencing, with Nimbus (NB.1.8.1) also circulating widely.
• UK Covid hospital admissions have risen to 2.73 per 100,000 and test positivity has increased, signaling early-season pressure on services.
• CDC data show growing US transmission, including high or very high wastewater signals in multiple states, with Stratus having expanded rapidly over the summer.
• WHO lists XFG as a variant under monitoring and assesses low global risk, with authorities finding no evidence of increased severity or reduced vaccine protection.
• Clinicians highlight hoarseness and an intense sore throat as common presentations, and guidance urges staying home if unwell, masking in crowded spaces, and getting the 2025–26 vaccine, which ACIP recommends for everyone 6 months and older.