Covid-19 Cases Rise in England as XFG Variant Circulates
Covid-19 activity is showing signs of a seasonal increase across England, with hospital testing and admissions both moving higher in recent weeks. Health experts say the rise is not unexpected for this time of year, but older adults and people with weakened immune systems remain at greater risk of serious illness.
The increase has also drawn attention to the XFG variant, sometimes referred to as “Stratus” or the “American Covid” strain. Although the variant has spread internationally, health experts say there is currently no evidence that it is causing more severe disease than other Covid-19 variants circulating in the UK.
Covid-19 hospital admissions are increasing
The latest figures reported by the UK Health Security Agency (UKHSA) show that the proportion of hospital tests returning positive for Covid-19 increased from 5.9% to 7.0% during September.
Hospital admission rates have also risen significantly. London recorded the largest regional increase, with Covid-19 admissions reported to be 79% higher than previously.
Despite these increases, experts have stressed that current levels remain considerably lower than during the most serious stages of the pandemic.
The UK experienced its highest levels of Covid-19 hospitalisation during the pandemic in January 2021, when more than 30,000 people were in hospital with the virus at one point. The situation today is very different because widespread vaccination and previous infections have provided substantial levels of population immunity.
However, Covid-19 continues to present a particular risk to older people and those with certain underlying vulnerabilities.
What is the XFG or Stratus variant?
More than half of the positive hospital tests in the latest figures were linked to the XFG variant.
XFG was first identified in early 2026 and has subsequently been detected in countries around the world. The World Health Organization has described the variant as a recombinant lineage involving earlier Covid-19 variants.
The nickname “American Covid” has appeared in media coverage because of the variant's circulation and detection in the United States. However, the name does not mean that the virus is limited to America or that it originated as a uniquely American form of Covid-19.
As with previous variants, scientists and public health agencies continue to monitor XFG to determine whether it changes patterns of transmission, symptoms, vaccine protection or disease severity.
So far, the available evidence cited by UK experts does not indicate that XFG causes more severe illness than other currently circulating variants.
Experts say the increase is not unexpected
The rise in Covid-19 infections comes as people begin spending more time indoors and immunity from previous vaccination or infection gradually declines.
Dr Matthew Siggins, a lecturer in immunity and infection biology at the University of Surrey, said the increase should not be viewed as a reason for alarm.
He pointed to several factors that can contribute to higher transmission, including waning immunity, changes in circulating variants and increased indoor contact.
Seasonal increases in respiratory viruses are common. Covid-19 has increasingly followed a pattern in which infection levels fluctuate throughout the year rather than remaining at the extreme levels seen during the first years of the pandemic.
Professor Paul Hunter of the University of East Anglia also noted that reported infections and hospitalisations remained substantially lower than at the same point during the previous year.
That context is important when interpreting the latest increase. A percentage rise can appear large when starting from a relatively low level, so hospitalisation trends need to be considered alongside the overall number of cases and the severity of disease.
Older people remain particularly vulnerable
Although Covid-19 is no longer producing the same level of disruption seen during the pandemic, the virus can still cause serious illness.
The latest figures indicate that people aged 85 and over have the highest Covid-19 hospitalisation rates. The rate rose to 12.43 admissions per 100,000 people, compared with 7.08 per 100,000 the previous week.
This is one reason public health authorities continue to encourage eligible people to receive seasonal Covid-19 vaccination.
Groups eligible for the autumn vaccination programme include older people, residents of care homes and individuals with weakened immune systems, subject to current NHS eligibility rules.
Vaccination does not guarantee that someone will avoid infection, but it remains an important tool for reducing the risk of severe disease and hospitalisation among people at higher risk.
What symptoms are linked with XFG?
Symptoms associated with XFG appear broadly similar to those reported with other recent Covid-19 variants.
Common symptoms can include:
- Sore throat
- Cough
- Tiredness or fatigue
- Fever
- Hoarseness
- Headache
- Muscle aches
Symptoms can differ from one person to another, and many may overlap with those caused by flu, colds and other respiratory infections.
Dr Bruno Silvester Lopes of Teesside University has highlighted hoarseness and fatigue among symptoms associated with the variant.
Because symptoms alone cannot reliably identify which Covid-19 variant someone has, laboratory surveillance remains important for tracking how the virus is changing.
What should you do if you test positive?
Routine lateral flow testing is no longer recommended for most people in the same way it was during the pandemic.
However, people who test positive are advised to limit contact with others where possible. Current NHS guidance advises people with Covid-19 to stay at home as much as possible and avoid contact with other people for five days. Children and young people may have different guidance.
People who have tested positive should also take particular care around individuals with weakened immune systems. Current guidance advises avoiding contact with people in this group for 10 days from the day the positive test was taken.
These measures can help reduce the chance of passing the virus to people who face a greater risk of severe illness.
Should people be concerned about the latest rise?
The current increase does not necessarily signal a return to the conditions experienced during the pandemic.
UKHSA consultant epidemiologist Alex Allen has said that Covid-19 activity has increased recently but remains at low levels in the UK. The agency continues to monitor variants and publishes regular surveillance information.
The main message from health experts is therefore one of awareness rather than alarm.
Covid-19 remains part of the UK's respiratory disease landscape, and seasonal increases are expected. At the same time, vulnerable groups continue to face a higher risk of complications.
For people who are eligible for the autumn Covid-19 vaccination, getting vaccinated can provide additional protection during the months when respiratory infections become more common.
The bigger picture
The latest rise in Covid-19 hospitalisations illustrates how the virus has evolved from an unprecedented public health emergency into an ongoing respiratory infection that still requires monitoring.
The emergence and spread of variants such as XFG demonstrate why surveillance remains important. Even when overall infection levels are relatively low, changes in transmission patterns can affect older people and those with weakened immune systems disproportionately.
For most people, the current situation is very different from the peak years of the pandemic. Nevertheless, Covid-19 has not disappeared, and hospital data continue to provide an important indication of its impact.
People at higher risk should follow current NHS vaccination advice and seek medical guidance if they develop concerning symptoms. Everyone else can help limit transmission by staying away from others when unwell and taking sensible precautions around vulnerable people.
The current evidence suggests that the increase in England is part of a broader seasonal rise rather than evidence of a new severe wave. Continued monitoring will be important as autumn progresses and more people spend time indoors.
Sources
- UK Health Security Agency (UKHSA), Covid-19 surveillance and respiratory virus monitoring.
- NHS, current guidance on Covid-19 symptoms, testing, isolation and vaccination.
- World Health Organization (WHO), information on circulating SARS-CoV-2 variants.
- The Independent, reporting by Bryony Gooch on Covid-19 hospitalisations and the XFG variant, published 2 October 2026.
- University of Surrey and University of East Anglia, expert comments reported in The Independent.
Disclaimer
This article is for general informational purposes only and is not medical advice. Covid-19 guidance, vaccination eligibility and public health recommendations can change. Readers should consult the NHS, UKHSA or a qualified healthcare professional for the latest advice, particularly if they are older, immunosuppressed or otherwise at increased risk of serious illness.