The first cases of a new Covid-19 variant have been detected in England as the virus spreads across Britain, the UK’s health agency has confirmed
The UK Health Security Agency (UKHSA) said 13 cases of Covid strain NB.1.8.1 had been recorded in England, with “small numbers” detected across the UK.
It’s unclear how many cases of the new strain, which now account for just over 10 per cent of global infections, have been recorded in Scotland, Wales or Northern Ireland.
Since first being recognised in January 2025, the omicron variant has spread to several states across the US, Australia, Thailand and is the most dominant variant in China and Hong Kong.
UKHSA deputy director Dr Gayatri Amirthalingam said it was unlikely to pose more severe disease than other variants.
Common symptoms align with typical Omicron subvariants and include fatigue, fever, muscle aches and a sore throat, according to the World Health Organisation.
But given the dwindling number of people testing for Covid-19, it has become increasingly difficult to know the true number of infections.
The World Health Organisation has designated the NB.1.8.1 as a “variant under monitoring”, and comprises around 10.7 per cent of all submitted sequences worldwide.
While it first appeared in samples at the beginning of this year, data from GISAID, a global data of genetic sequences of major disease-causing viruses, show that the first known cases were registered at the end of April.
Current Covid jabs are expected to remain effective against this variant and protect anyone infected from severe illness.
Dr Gayatri Amirthalingam, UKHSA deputy director, told The Independent: “It is normal for viruses to mutate and change over time. UKHSA is monitoring all available data relating to SARS-CoV-2 variants in the UK and abroad, and we continue to publish our findings in our regular Flu and COVID-19 surveillance reports.
“NB.1.8.1 has been detected in small numbers in the UK to date, but international data suggests that it is growing as a proportion of all COVID-19 cases.
“Based on the available information so far however, there is no evidence to suggest that this variant causes more severe disease than previous variants, or that the vaccines in current use will be less effective against it.”
