FOUR common Covid symptoms must be added to the official list after millions of cases were missed, experts have warned.
Sore throat, headache, fatigue and diarrhoea should be considered as main virus symptoms – on top of the classic persistent cough, fever and loss of smell or taste.
Scientists think this would help pick up about a third more cases of the bug, data gathered from the ZOE Covid Symptom Study app.
They believe millions of infections were delayed in being found or missed entirely as people wouldn’t get a test with these four symptoms.
PCR swab tests only allow for people to book in to see if they have the virus if they have the three NHS listed symptoms. But this form of testing is the most reliable.
Researchers say testing Brits with the three ‘classic’ symptoms would have spotted 69 per cent of symptomatic cases.
But they think testing people with any of the seven key symptoms in the first three days of illness, would find 96 per cent of symptomatic cases.
Professor Tim Spector, ZOE Covid Symptom Study project lead, said: “We’ve known since the beginning that just focusing testing on the classic triad of cough, fever and anosmia misses a significant proportion of positive cases.
“We identified anosmia as a symptom back in May and our work led to the government adding it to the list, it is now clear that we need to add more.
“By inviting any users who log any new symptoms to get a test, we confirmed that there are many more symptoms of Covid-19.
“This is especially important with new variants that may cause different symptoms. For us, the message for the public is clear: if you’re feeling newly unwell, it could be Covid and you should get a test.”
Dr Claire Steves, Reader at King’s College London and lead scientist on the ZOE Covid Symptom Study app said: “When PCR testing was scarcely available, it made sense to restrict it.
“Now in the UK we have plenty of tests available, thanks to so much effort by labs all over the country, and every positive person detected could save lives.
“We urge the government to expand the testing criteria so that anyone with new symptoms that might be Covid-19 should be able to get a test to help stop the spread of the virus.”
The researchers found 31 per cent of people with Covid-19 do not have any of the classic symptoms in the early stages of the disease, which is when they are most infectious.
Dr Jakob Cramer, head of clinical development at Cepi, said: “Accurate diagnosis of Covid-19 cases is crucial when assessing the efficacy of Covid-19 vaccine candidates in large-scale studies, especially since the signs and symptoms associated with the disease are extensive and overlap with other common viral infections.
“The findings of this study provide important insights that will help optimise the choice of triggering symptoms for diagnostic work-up in Covid-19 vaccine-efficacy trials.
“We hope the findings of this study will not only aid Cepi’s Covid-19 vaccine development partners but also the wider R&D community.”
Having any of these other symptoms alone was associated with Covid, or in combination with the classic signs.
The more symptoms people showed the more likely they were to test positive.
The findings come from swab tests and questionnaires collected between June 2020 and January 2021 as part of the Imperial College London-led REACT study.