Overview

• The World Health Organization has listed XFG as a variant under monitoring since June 25, 2025.
• Germany’s Robert Koch Institute estimates XFG accounts for about 80% of recent infections in the country.
• XFG is a recombinant of Omicron lineages LF.7 and LP.8.1.2, a composite origin that prompted the “Frankenstein” nickname popularized by British tabloids after earlier usage by virologist Alex Sigal.
• Clinical features mirror prior Omicron waves, with common symptoms including fever, cough and sore throat.
• Current data indicate vaccines continue to protect against severe disease and rapid tests detect infections, with officials urging boosters, home isolation when symptomatic and testing before contact with high‑risk people.