Doctors are warning anyone with a ‘razor blade’ throat that they could have a new and highly contagious Covid variant.

Dubbed ‘Nimbus’, the strain is descended from the super virulent Omicron, with 13 cases having already been found in the UK, following a surge in cases in China, Singapore and Hong Kong.

Whilst experts say Nimbus symptoms are broadly similar to earlier versions of the virus a ‘razor blade sore throat’ could be a key sign of the new variant.

According to Dr Naveed Asif, a GP at The London General Practice, this distinctive symptom is characterised by a sharp, stabbing pain when swallowing, often at the back of the throat.

Other symptoms linked to the strain include redness in the back of the mouth and swollen neck glands, as well established common Covid symptoms like fever, muscle aches and congestion.

‘However, symptoms can vary widely so vigilance is key’, Dr Asif told Manchester Evening News.

According to the NHS, Covid symptoms include a high temperature, a new continuous cough, a loss or change to sense of smell or taste, shortness of breath and feeling sick.

Whilst only 13 British cases of Nimbus have been identified so far, this figure likely underestimates how far the variant has spread.

This is because the number of Covid tests carried out has massively decreased since the height of pandemic and lockdown.

Data from the UK Health Security Agency (UKHSA) shows the number of people testing positive for Covid has hit record levels this year and is already 97 per cent higher than numbers recorded in March.