A fresh coronavirus variant, NB.1.8.1, has emerged, making its way into the UK and stirring global health discussions once more, over five years after the pandemic first swept across the world.
The new COVID variant NB.1.8.1 has already been confirmed in Northern Ireland and Wales, and it’s now responsible for more than 10% of infections worldwide. This latest strain appears to have a growth advantage over previous ones, sparking concern among health experts globally.
What is the NB.1.8.1 Variant?
According to the World Health Organization (WHO), NB.1.8.1 has been designated as a “variant under monitoring.” It accounts for approximately 10.7% of all sequenced COVID-19 cases across the globe, as submitted to GISAID, a global database for virus genetics.
A WHO spokesperson stated: “SARS-CoV-2 continues to evolve, and between January and May 2025, there were shifts in global SARS-CoV-2 variant dynamics. At the beginning of the year, the most prevalent variant tracked by WHO at the global level was XEC, followed by KP.3.1.1.”
“In February, circulation of XEC began to decline while that of LP.8.1 increased, with the latter becoming the most detected variant in mid-March. Since mid-April, the circulation of LP.8.1 has been slightly declining as NB.1.8.1 is increasingly being detected.”
This new COVID variant NB.1.8.1 initially surfaced in early 2025 but was only officially identified through genomic data submitted in April.
Symptoms of the NB.1.8.1 Variant
Although NB.1.8.1 appears to spread more easily than older variants, experts say there is no sign it causes more severe illness.
“Data indicates that NB.1.8.1 does not lead to more severe illness compared to previous variants, although it appears to have a growth advantage, suggesting it may spread more easily,” explained Professor Subhash Verma of the University of Nevada, Reno School of Medicine.
This indicates the new COVID variant NB.1.8.1 is more transmissible, but not necessarily more dangerous.
Commonly Reported Symptoms
- Fatigue
- Fever
- Muscle aches
- Sore throat
- Gastrointestinal symptoms: nausea, diarrhoea, constipation
Such symptoms are consistent with existing Omicron subvariants, though the added digestive issues are drawing attention.
Where Has NB.1.8.1 Been Detected?
Alongside the confirmed cases in Wales and Northern Ireland, the new COVID-19 variant NB.1.8.1 is being seen in countries including:
- The United States
- Australia
- Thailand
- China and Hong Kong, where it’s currently the dominant strain
Its global footprint is expanding steadily, though exact numbers are hard to verify due to a drop in regular COVID-19 testing.
Do Vaccines Protect Against NB.1.8.1?
Encouragingly, current COVID-19 vaccines are believed to still provide effective protection against this variant. While they may not stop every infection, they are expected to reduce the risk of serious illness or hospitalisation.
Experts continue to monitor vaccine performance, but at this stage, there is no evidence suggesting NB.1.8.1 can evade vaccine-induced immunity in a significant way.
What You Need to Know About NB.1.8.1
- The new COVID-19 variant NB.1.8.1 is a fast-spreading Omicron offshoot
- Symptoms are generally mild but may include gut issues
- Found in the UK, US, China and more
- Vaccines remain effective against serious illness
- WHO is monitoring its global spread
As the new COVID variant NB.1.8.1 circulates more widely, public health bodies are keeping a close watch. While not yet a variant of concern, its growth suggests it could shape the next phase of the pandemic. For now, awareness and vaccination remain key tools in the ongoing fight against COVID-19.
