A new Covid strain called NB.1.8.1, has been found circulating in the UK with health officials giving advice to people who have symptoms to remain at home if possible
Brits with Covid symptoms have been given advice to “stay at home” by top health officials as a new variant has been found circulating in the country with an increase in hospital admissions.
The new strain, called NB.1.8.1, has been detected in small numbers in the UK, with 13 confirmed cases in England, according to UK Health Security Agency data from PCR-positive Covid samples. The latest UKHSA data shows Covid-19 activity increased slightly in England between May 26 and June 1. Weekly hospital admissions from the virus slightly increased to 1.49 per 100,000 patients, compared with 1.40 per 100,000 in the previous week.
Dr Gayatri Amirthalingam, UKHSA Deputy Director, said: “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.”
NB.1.8.1 was added to a World Health Organisation (WHO) watch list on May 23. It is one of six Covid-19 variants currently being monitored by the organisation.
The new strain was first recorded on January 21. By late April 2025, it made up roughly 10.7 per cent of all global infections – up from just 2.5 per cent four weeks prior, according to the WHO.
The WHO said in a statement that the strain could potentially be more transmissible than previous variants. However, it does not appear to cause worse symptoms or more serious illness.
UKHSA Covid advice to Brits
There are currently no Covid-19 restrictions in the UK, the UKHSA says. The WHO has said it is not advising that travel restrictions are imposed in light of the new variant.
It stated in a report: “WHO recommends that countries remain vigilant, adapt to evolving epidemiological trends, and leverage COVID-19 management strategies to strengthen systems for all respiratory disease threats.
“Member States should continue offering COVID-19 vaccines in line with WHO recommendations. Based on the current risk assessment of this event, WHO advises against imposing travel or trade restrictions.”
The UKHSA advises people with symptoms of Covid, a high temperature, or who do not feel well enough to go to work, school, childcare, or do normal activities to “avoid contact with vulnerable people and stay at home if possible”.
It said in a blog post: “The most important thing to do is to get your vaccination when it is due if you’re eligible.” The UKHSA added: “Vaccines remain our best defence against severe disease and hospitalisation from flu and COVID-19.”
It says the spring 2025 Covid booster programme remains open to eligible groups until June 17, who can book via the NHS App, website or by phoning 119.
What are the symptoms of Covid NB.1.8.1?
Symptoms of the new strain are believed to be the same as earlier variants of the Covid virus. The NHS says common symptoms of Covid-19, which are very similar to symptoms of other illnesses, such as colds and flu, include:
- A high temperature or shivering (chills)
- A new, continuous cough
- A loss or change to your sense of smell or taste
- Shortness of breath
- Feeling tired or exhausted
- An aching body or a headache
- A sore throat, blocked or runny nose
- Loss of appetite, feeling sick or being sick
- Diarrhoea
According to the NHSM, most people with Covid feel better within a few weeks, but it can take longer to recover. For some people, it can be a more serious illness and their symptoms can last longer.