
Covid-19: XFG the Nimbus Variant Covid-19 Nimbus
A new strain of Covid-19, known as XFG or the Stratus/Nimbus variant, is now circulating widely in the UK.
This variant is responsible for around 30–40% of current Covid cases in England. XFG is a subvariant of Omicron and is notable for its unique symptom: a hoarse or scratchy voice, which sets it apart from earlier strains.
While XFG spreads quickly and shows some ability to evade immunity from previous infections or vaccinations, current evidence suggests it does not cause more severe illness or higher death rates than earlier variants.
Health experts and the World Health Organization consider the public health risk from XFG to be low and vaccines in use are still expected to offer protection against serious illness.
The next round of NHS Covid-19 vaccinations in the UK is scheduled for autumn and winter 2025/26.
The programme will run from 1 October 2025 to 31 January 2026, with most vaccinations expected to be completed by 19 December 2025 to provide the best protection ahead of winter.
For the autumn 2025 Covid-19 vaccination programme, the following groups are eligible for a free NHS Covid-19 vaccine:
This eligibility applies across all four nations of the UK (England, Scotland, Wales, and Northern Ireland).
If you are eligible, you do not need to wait for an invitation and can book once the programme opens.
The NHS will provide further updates as the autumn campaign approaches, so check the NHS website for the latest information.