Red-flag Covid symptom of Stratus and Nimbus variants and who is eligble for free vaccine

If you feel unwell and have a temperature you may well have caught one of the new strains of Covid circulating this autumn - but there's another nasty tell-tale symptom to look out for.

XFG, dubbed Stratus, and NB.1.8.1, known as Nimbus, are now the most common variants being passed around in the UK.

Experts say recent genetic changes the virus has acquired may make infections more likely.

But while experts say these do not appear to pose any bigger threat than previous types of Covid or make people feel more ill, there is one symtom which is rather nasty and probably means you have one of these variants.

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It is usual for viruses to evolve as they spread between people over time but when the changes become significantly different, the new virus types are known as variants.

If you have a razor blade sore throat you could have one of these new variants. A hoarse voice or a "razor blade" sore throat is thought to be a tell-tale symptom of the latest types.

But that's not the only sign - Covid can still cause a wide range of symptoms, including headache, coughing, a blocked or running nose and exhaustion.

If you think you have Covid you should avoid contact with vulnerable people and stay at home if possible.

If you have symptoms and need to leave the house, you should wear a face covering. Washing hands regularly and using and disposing tissues in bins can reduce the spread of this and other respiratory illnesses.

And if you have a sore throat, drinking plenty of fluids and having a teaspoon of honey may help ease symptoms. According to the Royal College of GPs, rates of Covid are now increasing across the UK especially in the very young and elderly.

Meanwhile, people over 75 can get a free vaccine against Covid on the NHS. This can offer good protection, even against the new variants, says the UK Health Security Agency (UKHSA).

It's urging people to book their vaccinations against flu and another common winter virus called RSV (respiratory syncytial virus) as cases start to increase ahead of winter.

"It's normal for viruses to mutate and change, and as more data becomes available on these variants, we'll have a better understanding of how they interact with our immune systems and how to optimise our protection, as well as actions we can take to keep the most vulnerable safe and live our lives as normally as possible," says the UKHSA. "The most important thing is for those eligible to get their vaccination when it is due."

It's possible to catch Covid again even if you have had it very recently, or have been vaccinated. Reinfections are usually mild, but you can feel unwell and still spread the virus to others. Covid tests are no longer widely available for free, but pharmacies still sell them.

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