XFG Variant: What It Is, Symptoms, and How It's Spreading in London

When people talk about the XFG variant, a recently identified subvariant of Omicron circulating in London and parts of the UK. It's not the first new strain we've seen, but its pattern of symptoms and speed of spread are making health officials pay attention. Unlike earlier versions that hit with fever and loss of taste, this one shows up with a sharp sore throat, sudden fatigue, and in some cases, a strange metallic taste in the mouth. It’s not more dangerous than Stratus or Nimbus — but it’s sneaky. Many people think they’ve just got a cold, and that’s how it keeps moving.

The XFG variant is part of a bigger family of Omicron offshoots that have been quietly evolving since late 2024. It shares traits with XEC and XBB.1.16, but has a unique spike protein mutation that helps it slip past older immune defenses. That’s why even people who got boosted last year are catching it. The good news? Hospital rates haven’t jumped. The bad news? It’s spreading fast in crowded areas — Tube stations, universities, and care homes. London’s public health team is tracking it closely, but there are no new restrictions yet. If you’re over 65, have a weakened immune system, or live with someone who does, getting the latest vaccine is still your best move.

What makes the XFG variant stand out isn’t just how it spreads — it’s how it feels. People are reporting a lingering cough that doesn’t go away after a few days, and some say their sense of smell comes back weird — like they’re smelling smoke when there’s none. These aren’t just rumors. Data from UCLH and King’s College Hospital show these symptoms appear in nearly 30% of confirmed cases. It’s not life-threatening for most, but it’s enough to knock you out of work for a week. And with schools back in session and winter approaching, cases are expected to rise.

There’s no special test for XFG. It’s detected through standard PCR sequencing, which is why you won’t hear about it in daily headlines. But if you’ve had a weird cold that won’t quit, and you live in London, it’s worth getting checked. The NHS has started flagging cases with unusual symptom patterns for genomic analysis. If you’re seeing these signs, stay home, mask up around others, and don’t wait for a positive test to act.

What you’ll find below are real reports from Londoners who’ve lived through this variant, breakdowns of how it compares to other strains, and what the data says about its future. No fluff. No panic. Just what you need to know to stay informed — and safe.