There are many more early symptoms of COVID than the three listed in NHS advice, with men and women likely to show different signs of infection, a study has found.
Research conducted by the Zoe COVID app, which is used to study the symptoms of COVID-19 and track the spread of this virus, found that loss of smell, chest pain, persistent cough, abdominal pain, blisters on the feet, eye soreness and unusual muscle pain were the most common signals of early infection.
Since the emergence of coronavirus in the UK in February 2020 the NHS has listed a persistent cough, high temperature, and loss of sense of taste or smell as the key symptoms that signal infection.
Men are more likely to develop a fever in the early days of coronavirus whereas women report loss of smell more frequently, the study found.
Principal investigator of Zoe COVID app, Professor Tim Spector, has repeatedly urged the government to add additional symptoms to the official guidance in order to pick up more infections.
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The report said: "Early testing for COVID-19 is critical to avoid spread during the most infectious period, however different combinations of symptoms are felt among different population groups.
"Younger patients may present with different symptoms compared to older populations, and men can have different symptoms to women in the early stages of COVID-19 infection."
The differences between men and women
According to the research, men were more likely to report shortness of breath, fatigue, chills and fever in the early stages of infection, whereas women were more likely to report loss of smell, chest pain and a persistent cough.
The data showed that the clearest symptoms for early detection of COVID-19 overall included loss of smell, chest pain, persistent cough, abdominal pain, blisters on the feet, eye soreness and unusual muscle pain.
However, for older groups, loss of smell was not an early sign, whereas other early symptoms such as diarrhoea were more common.
And a high temperature, while a known symptom of COVID-19, was not an early indicator in any age group.
Prof Spector, said of the findings: “ZOE continues to drive the public health message that there are more than just three symptoms of COVID.
"Our data shows symptoms are more mild and comparable to that of a bad cold, with a runny nose, headache and a sore throat among the top symptoms for all groups. It seems unlikely that the government is going to change the official list anytime soon, so we are calling on people to spread the word.
"If you or anyone in your household feels ill, do a lateral flow test and if you test positive, confirm it with a PCR test. It’s simple, if you feel ill, take a test.”
And Dr Liane dos Santos Canas, of King’s College London, who analysed the data, said: “Currently in the UK only a few symptoms are used to recommend self-isolation and further testing.
"Using a larger number of symptoms and only after a few days of being unwell, using AI, we can better detect COVID-19 positive cases. We hope such a method is used to encourage more people to get tested as early as possible to minimise the risk of spread.”
In June data from the app revealed the most reported signs of coronavirus infection for those with at least one vaccine jab include a headache, runny nose, sore throat, sneezing and persistent cough. For those double-vaccinated, the symptoms are similar, except there isn't a persistent cough in the top five.
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