Scientists have warned of four new signs of Covid and Long Covid as a new variant of the disease is found to be dominant in the UK.
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.
Meanwhile, hair loss and a reduced sex drive have been added to the list of symptoms caused by Long Covid.
Senior author Dr Shamil Haroon is associate clinical professor in public health at the University of Birmingham, which analysed anonymised electronic health records of 2.4million Brits - 486,000 who had caught Covid.
He said: “This research validates what patients have been telling clinicians and policy makers throughout the pandemic - that the symptoms of Long Covid are extremely broad and cannot be fully accounted for by other factors such as lifestyle risk factors or chronic health conditions.
“The symptoms we identified should help clinicians and clinical guideline developers to improve the assessment of patients with long-term effects from Covid-19, and to subsequently consider how this symptom burden can be best managed.”
The most common symptoms include loss of smell, shortness of breath and chest pain - others included loss of libido and hair.
People who tested positive for the virus reported 62 symptoms much more frequently 12 weeks after initial infection than those who had not contracted the virus, the study found.
The findings come as Omicron BA.5 is now the dominant Covid strain, accounting for approximately 79 per cent of UK cases as of July 18.
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."
He added: "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."
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 last week, confirms an estimated 78.7 per cent of confirmed cases in England are BA.5 which was first identified in April and was designated as a Variant of Concern on May 18.
Prof Spector said at the time: "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."
