A major COVID-19 study has revealed new symptoms associated with coronavirus.
A study of more than 1 million people in England has revealed chills, loss of appetite, headaches and muscle aches have been reported as coronavirus symptoms.
Researchers said on Wednesday it potentially means thousands of COVID cases are not being picked up by the testing system, because these symptoms don’t match the ones currently set out by the NHS to qualify for a test.
Those three “classic” symptoms are a high temperature, a new continuous cough, and a loss or change to sense of smell or taste.
The research is based on swab tests and questionnaires collected between June last year and January this year as part of the Imperial College London-led React study.
Yahoo News UK has approached the Department of Health for comment on the study's findings.
The study said that having any of the “new” symptoms or the classic ones – either alone or in combination – was associated with COVID infection. The more symptoms people showed, the more likely they were to test positive.
The researchers estimated that about 50% of symptomatic cases are currently being picked up, based on people getting tested for any of the classic symptoms.
However, they estimated this would increase to 75% if the “new” symptoms were included to qualify for a test.
Prof Paul Elliott, director of the React programme, said: “These new findings suggest many people with COVID-19 won't be getting tested – and therefore won't be self-isolating – because their symptoms don’t match those used in current public health guidance to help identify infected people.
"We understand that there is a need for clear testing criteria, and that including lots of symptoms which are commonly found in other illnesses like seasonal flu could risk people self-isolating unnecessarily.
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“I hope that our findings on the most informative symptoms mean that the testing programme can take advantage of the most up-to-date evidence, helping to identify more infected people.”
The number of COVID symptoms has been debated throughout the pandemic.
At the start of the outbreak in spring last year, the UK only listed a high temperature and a new continuous cough as symptoms people should look out for. A loss or change to sense of smell or taste was added to the list in May.
Last month, meanwhile, more than 140 GPs signed an open letter to England’s chief medical officer Prof Chris Whitty and Public Health England's Dr Susan Hopkins asking the UK to bring its official COVID symptoms in line with the World Health Organization.
The letter, published in the British Medical Journal, said a runny nose, a sore throat and a headache should be added to the official list.
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