Thousands of new cases of the latest coronavirus strain - known as XFG or American Covid - have been recorded in the UK just ahead of flu season. The UK Health and Security Agency (UKHSA) reported that positive cases of the virus in hospital settings had risen from 5.9 percent to 7 percent in a few weeks.
The UKHSA recorded 1,374 cases in August, but by September that figure jumped by 230 percent to 4,589. Hospitalisations rose from 950 in August to 4,939 the following month.
Hallmark symptoms of the variant
According to Stony Brook Medicine, most people will experience mild cases of American Covid, especially if they have received the vaccination or a booster. The university advised people to watch for potential symptoms, given that many vulnerable people could still be adversely affected.
Hallmark symptoms include a persistent dry cough, fatigue or general tiredness, and a high temperature of 38C or above. The variant may present with more than half a dozen other signs, ranging from a scratchy, sore throat to bouts of diarrhea.
Other potential symptoms and emergency signs
Other potential symptoms include shortness of breath, feeling sick (nausea), loss of appetite or stomach aches, headaches and muscle pain, brain fog or trouble concentrating, diarrhea, and sinus congestion or a runny nose.
There are signs that warrant emergency attention. The NHS warns that people who experience the following should immediately dial 999: feeling very suddenly and severely unwell with symptoms only continuing to get worse; sudden chest pain; intense breathlessness that prevents finishing even short sentences while resting; breathing suddenly getting worse; coughing up blood; collapsing, fainting, or other loss of consciousness, and experiencing a seizure for the first time; inability to wake or stay awake; new confusion; lips, nail beds and skin appearing pale, gray or blue - depending on skin tone; and a rash that behaves like meningitis - it does not fade when a glass is rolled over it.
Advice for those who test positive
Brits who fear they may have contracted the virus have been advised to take steps to avoid spreading it further. They have been asked to avoid contact with other people for at least five days, with anyone younger than 18 asked to wait at least three days. Anyone who tests positive should avoid meeting with anyone who has a weakened immune system for at least 10 days after the day the results came back.
The vast majority of people who contract Covid will not develop severe symptoms, and extreme cases can be prevented by getting the vaccine or booster. Those who have experienced the latest version have reported feeling unwell and bedbound.
One social media user who fell ill in September said: "I had all them symptoms bar one earlier this week. I was in bed for 30+ hours knocked me on my a*** whatever it was."
Another added: "I have been really ill for about 6 weeks and the past 2 weeks on top of that been extra knocked out i.e feel like I have been heavily drinking, sniffles etc. Had a burning sensation at back of my mouth for 2 weeks very badly and since then mildly."
Officials have said that, despite the rise in recent cases, Covid infections remain generally low across the UK. Alex Allen, consultant epidemiologist at the UKHSA, said: "While Covid-19 activity has shown some recent increases, cases remain at low levels in the UK.
"UKHSA is monitoring all the data relating to Covid-19 variants in the UK and abroad, and we continue to publish our findings in our regular surveillance reports."
Stratus Covid has long been circulating around the world and was identified as another outbreak in the US last year. While it is named after the US, it likely didn't originate there, as doctors believe it first established a foothold in Southeast Asia in 2025 before touring the rest of the world.
Dr Magdalena Sobieszczyk, chief of the Division of Infectious Diseases at NewYork-Presbyterian/Columbia University Irving Medical Center, said when the virus was making the rounds last year that it is a variant that can be transmitted particularly easily. She said: "Stratus has been around in Southeast Asia since January of this year, and came to the United States around the spring.
"We've been seeing an uptick since July, predominantly because it's a variant that can be transmitted easily and people were travelling a lot more, vaccine uptake has not been very high, and now many people are returning to school and their regular routines."
XFG is currently one of several different Covid strains in circulation, with three others - BA.3.2, NB.1.8.1, and PQ.16.1.1 - also identified by the World Health Organisation (WHO). They are circulating ahead of flu season, which typically begins around early October.
