A professor has warned people to assume they have Covid if they wake up with two telltale symptoms.
Fatigue in the morning, even after a good night's sleep, and a sore throat may be a sign you have the virus.
Professor Tim Spector said a sore throat is more commonly reported in people with coronavirus than a regular common cold.
If you spot these two symptoms you should "assume" it's Covid, he wrote.
Professor Spector, who heads up the ZOE Health Study, tweeted: "Twice as many covid cases as common colds currently- the ratio has never been so high.
"Symptoms much the same except generally more fatigue and sore throat - so best to assume it’s Covid!
"Hopefully this wave will be over soon."
Prof Spector said: "Try and get tested if you can. If you can't get tested, assume you've got a cold and stay away from other people until you feel better."
Last week he said: "New study suggests that new BA4 and BA5 variants work by both evading the existing immune defences and also neutralising some of them. No surprise they are so successful as UK cases soar to record levels."
A new Covid variant has been found to be dominant in the UK as it causes widespread waves of infection across the globe.
Omicron BA.5 is now the dominant Covid strain, accounting for approximately 79% of UK cases as of 18 July.
Omicron BA.2.75 has been categorised as a separate variant to other BA.2 variants, but not as a Variant of Concern.
The latest UK Health Security Agency (UKHSA) Covid 19 variant technical briefing, published yesterday, confirms an estimated 78.7% of confirmed cases in England are BA.5 which was first identified in April and was designated as a Variant of Concern on 18 May.
