New COVID Variants Nimbus and Stratus Fuel Autumn Surge in Cases Across the UK

If you’re feeling unwell with a sore throat and fever this autumn, there’s a growing chance you may have caught one of the new COVID-19 variants now circulating widely across the UK. Health officials have identified two new strains—NB.1.8.1, nicknamed Nimbus, and XFG, referred to as Stratus—as the most prevalent COVID variants currently spreading among the population.

While early data suggests that these variants are not more dangerous or severe than earlier strains of the virus, they are contributing to a noticeable uptick in cases. Hospital admissions linked to COVID are also on the rise, particularly among vulnerable groups such as the very young and the elderly.

According to the Royal College of General Practitioners (RCGP), the overall rate of COVID infections is increasing steadily across the UK, a trend that aligns with seasonal patterns seen in previous years. Autumn and winter have historically seen a rise in respiratory illnesses, and COVID is proving to be no exception, especially as the virus continues to mutate and evolve.

What Makes Nimbus and Stratus Different?

Both variants—Nimbus (NB.1.8.1) and Stratus (XFG)—are sub-lineages of Omicron, the dominant strain over the past couple of years. As with most viruses, COVID-19 continues to mutate as it spreads from person to person. While these genetic changes are a normal part of viral evolution, when the mutations become significant enough, the virus is classified into a new variant.

Experts say that while Nimbus and Stratus do not appear to cause more severe illness than previous forms of COVID, their genetic changes may help them spread more easily. This could mean more people catching the virus, even if they’ve had COVID recently or are fully vaccinated.

Dr Alex Allen, a consultant epidemiologist at the UK Health Security Agency (UKHSA), reassured the public: “Based on the available information so far, there is no evidence to suggest that the variants cause more severe disease or that the vaccines in current use will be less effective against them.”

Recognising the Symptoms

One of the notable features of these new variants is the potential for slightly different or more pronounced symptoms. While COVID-19 still presents with a wide array of symptoms—such as coughing, headaches, fatigue, and congestion—some people with Nimbus or Stratus are reporting a “razor blade” sore throat, a hoarse voice, and more persistent upper respiratory discomfort.

“It’s hard to tell at first if you’ve caught COVID, the flu, or just a common cold,” said a spokesperson for the NHS. “But if you’re experiencing a bad sore throat, fever, and general exhaustion, it’s best to err on the side of caution.”

Common symptoms associated with the latest variants include:

Sore throat (often described as sharp or painful)

Hoarseness or voice changes

Fever or chills

Headache

Cough

Nasal congestion or runny nose

Fatigue or exhaustion

Muscle aches

Because the symptoms can so closely resemble those of other respiratory viruses, it can be difficult to tell what you have without a test.

What Should You Do If You Feel Unwell?

If you develop symptoms of COVID-19, especially if you’ve recently been around others who are sick, health officials still recommend basic precautions:

Stay at home if possible, especially if you have a fever or feel unwell.

Avoid contact with vulnerable individuals, such as elderly family members or those with compromised immune systems.

Wear a face covering if you need to go out in public.

Wash your hands frequently, and use tissues to cover your mouth and nose when coughing or sneezing—dispose of used tissues in the bin immediately.

For sore throat relief, the NHS advises drinking plenty of fluids and trying a teaspoon of honey to soothe irritation. Over-the-counter remedies may help ease other symptoms like headaches and congestion.

Reinfection and Immunity

One of the challenges with COVID is that reinfections are still possible—even shortly after recovering or being vaccinated. While most reinfections tend to be mild, they can still result in uncomfortable symptoms and carry a risk of transmission to others.

“There’s a misconception that if you’ve had COVID recently, you’re safe for a while,” Dr Allen noted. “But immunity—whether from past infection or vaccination—does wane over time, and new variants may partially evade those defences.”

Can You Still Get a COVID Test or Vaccine?

Free COVID-19 testing is no longer widely available to the general public in the UK, but rapid tests can still be purchased from most pharmacies and high street retailers. Prices vary, but most home test kits are relatively affordable.

Vaccinations are still a key line of defence against COVID-19 and its variants. The NHS is currently offering free booster vaccines to high-risk groups, including:

People aged 75 and over

Residents of care homes for older adults

Individuals with certain health conditions that make them more vulnerable

The UKHSA says that the vaccines remain effective at preventing severe illness, even with the emergence of Nimbus and Stratus. People eligible for vaccination are strongly encouraged to get their jab as soon as possible, particularly with winter approaching.

The NHS is also promoting flu vaccines and new RSV (respiratory syncytial virus) vaccines, especially for older adults and young children who are more likely to suffer serious complications from these seasonal viruses.

Private clinics and pharmacies also offer COVID-19 vaccines, with prices typically ranging from £50 to £99 per dose, depending on location and availability.

Looking Ahead

While the emergence of new variants like Nimbus and Stratus may cause concern, health officials are emphasizing calm and caution rather than alarm. The most important tools—vaccination, testing, hygiene, and personal responsibility—remain effective.

“It’s normal for viruses to mutate and change,” the UKHSA said in a statement. “As more data becomes available on these variants, we’ll better understand how to protect ourselves and others.”

The message from the experts is clear: stay informed, follow public health guidance, and, above all, take precautions if you feel unwell.

Autumn may bring cooler weather and shorter days, but with the right measures, it doesn’t have to bring another major COVID wave.