EVERYTHING YOU NEED TO KNOW ABOUT LATEST COVID-19 VARIANT

The new Nimbus strain is similar to Omicron but may spread slightly more easily

- By CAMILLA FOSTER

For many of us, Covid-19 feels like a chapter we've closed but the virus hasn't completely vanished.

In fact, new variants continue to quietly circulate. One of the latest to appear on the radar is NB.1.8.1. So far it's only been detected in small numbers within the UK, but the UK Health Security Agency (UKHSA) says international data indicates the sub-variant is steadily accounting for a growing share of global Covid-19 cases.

What is the new variant and where has it come from?

“The NB.1.8.1 variant, also referred to as Nimbus, is a new strain of the Covid-19 virus that has emerged due to mutations in its genetic material,” says Dr Naveed Asif, GP at The London General Practice.

It's a sub-variant of Omicron, says Dr Chun Tang, GP at Pall Mall Medical, who explains: “Variants like this pop up when the virus mutates, which is normal for viruses, especially ones that spread widely.

“NB.1.8.1 was first picked up in early 2025 and has since been detected in several countries, including the UK, China and US.