UK Braces for New Covid Wave as ‘Nimbus’ Variant Spreads Rapidly
Scientists have warned that the UK is likely to experience a new Covid wave this summer as the highly contagious ‘Nimbus’ variant spreads rapidly around the world. According to The i Paper, the NB.1.8.1 variant, also known as Nimbus, is thought to be more contagious than other active Covid variants, although there is no evidence that the symptoms are any more severe.
The immunity built up by Britons from jabs and previous infections has waned considerably over the last six months, with relatively few cases of Covid and a prolonged period of low vaccination levels. As a result, scientists are concerned that the Nimbus variant could push up cases in the UK, following surges in China, Singapore, and Hong Kong.
Data from the COVspectrum database shows that the Nimbus variant has already spread rapidly in the UK, with its share of new Covid infections jumping from 2 per cent on April 28 to 11 per cent on May 12. While new infections are still well below the peaks seen last summer and autumn, there are signs that cases are starting to pick up in the UK.
New figures from the UK Health Security Agency (UKHSA) indicate that new Covid infections rose by about 7 per cent in the week to Sunday, June 1, and are around 80 per cent higher than at the start of March. Professor Lawrence Young, a virologist at Warwick University, told The i Paper that a spike in infections is expected over the next month or two.
"We are very likely to see a spike of infections over the next couple of months, possibly by later this month or in July," Professor Young said. "But it’s difficult to predict the level of this infection wave. Population immunity, either from vaccination or previous infection, is waning and, unlike other respiratory viruses such as flu, the Covid virus continues to spread in hot and humid weather."
The Nimbus variant has driven surges of infection in Asia over the spring and is now the dominant strain in Hong Kong and China. It is also spreading in the US and Australia. Preliminary evidence from lab studies suggests that NB.1.8.1 can infect cells more efficiently than previous variants and that it can partially evade the immune protection provided by antibodies from vaccinated or previously infected people.
According to the World Health Organisation (WHO), NB.1.8.1 now accounts for 10.7 per cent of global infections. The variant was first recognised in January 2025, and the WHO has designated it as a "variant under monitoring". This means the WHO is closely tracking the virus for signs that it could pose a significant threat to the public in the future, but it has not yet elevated it to "variant of concern" status.
Professor Young urged those who are eligible to take up their booster vaccines, as the World Health Organisation has said that jabs still offer good protection against severe disease from infections by the Nimbus variant. Free vaccines are still available for people aged 75 years and older, residents in care homes for older people, and those aged six months and over with a weakened immune system until June 17 in the current spring booster campaign.
Other experts, including Professor Christina Pagel, a healthcare data analyst at University College London, and Professor Steve Griffin, of Leeds University, also warned that a large wave of infection is possible in the coming months. Professor Paul Hunter, of the University of East Anglia, said: "I guess we will see some increase in reported infections. I doubt case numbers will be as high as this time last year, though I cannot be 100 per cent certain on this. But we do need to follow its progress."
The UKHSA reported that 5.9 per cent of those people with respiratory symptoms testing for Covid in hospitals tested positive in the week to Sunday. While the positivity rate is much lower than the peak seen last July, scientists say it gives a good indication of trends across the four nations.
To mitigate the spread of the virus, the public is advised to take up their booster vaccines if eligible, and to continue following public health guidance. The spring booster vaccine campaign runs until June 17 in England, and June 30 in Scotland, Wales, and Northern Ireland. Those ineligible for an NHS booster can also purchase vaccines.
As the UK prepares for a potential new Covid wave, The i Paper will continue to provide updates and analysis on the situation.
