The government has failed to update what symptoms people develop when they have COVID, despite a drastic change in the symptoms being reported, a top scientist has said.
Tim Spector, the head of the ZOE symptom study app, said the government and Public Health England had been ignoring the top five COVID symptoms since May and that the issue is leading to "tens of thousands of extra cases and long COVID."
The Zoe app collects data from more than 4 million contributors to help track multiple aspects of the virus - including the most common symptoms associated with those who have caught it.
In May, Prof Spector called on the government to update its list of most common symptoms , saying sneezing should be included. He said other signs of infection were headache, runny nose and sore throat.
"It is about time the government, after a year and a half, change the list of classic symptoms," he said at the time. "We do need a much broader flexible approach to this as the virus changes and the populations change."
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Tweeting on Thursday ahead of the government's planned unlocking of England on 19 July, Prof Spector re-iterated his call: "Govt and PHE ignoring the top five symptoms since May as shown regularly on the ZOE CS is leading to tens of thousands of extra cases and Long Covid. Wouldn't be surprised to see some compensation claims."
The government still uses the same three symptoms it used early on in the pandemic when advising people to get a test, but only one of them features on the top five list of symptoms recently reported.
The US Centers for Disease Control and Prevention lists 11 more symptoms than the UK, and the World Health Organization (WHO) includes nine more.
Doctors have been warning the narrow three symptom definition of COVID by the government could mean many cases are being missed.
What are the COVID symptoms and what symptoms does the government use?
According to the Zoe Symptom study app, as of 23 June the top five symptoms for COVID-19 are:
Sore throat (58%)
Runny nose (57%)
Persistent cough (42%)
The symptoms changed slightly for people who have had two doses of the jab, for them the top five COVID-19 symptoms were:
Runny nose (66%)
Sore throat (47%)
Loss of smell (43%)
The government and the NHS use just three symptoms when advising people to get a test, they are:
Loss of smell or taste
None of the top three symptoms found in the COVID study feature in the government's list, with headache sore throat and runny nose now the most common symptoms.
For the unvaccinated, the government's defined symptoms are way down the list according to the ZOE study, fever is fourth, persistent cough is fifth, with loss of smell in ninth place.
It's a similar study for the double vaccinated with loss of smell is fifth, persistent cough in eighth and fever in twelfth.
Why hasn't the government updated their list?
At first the government adopted a list of the most common symptoms of the time, but they deliberately kept the list short in order to reduce the number of people seeking tests when tests were limited.
Now that testing is prevalent it is unclear why the government hasn't changed their definition of COVID symptoms.
In a letter in the British Medical Journal, a group of top doctors including Professor Calum Semple who is a member of the Government scientific advisory group on emergencies said the limited definition was leading to many cases being missed.
They suggested this could "hamper efforts to interrupt transmission" of the virus.
The group argued that increasing the symptom list could improve Britain’s pandemic response by expanding the criteria for self-isolation and eligibility for symptomatic testing.
They said the "narrow" case definition "limits" the early detection of contagious people, which restricts the efforts of the Test and Trace programme.
Non-traditional symptoms "often manifest earlier", they added.
The authors wrote: "The UK’s decision to adopt a narrow case definition was based on ease of communication, avoiding confusion with other infections and preserving testing capacity. This situation is now different — testing capacity is high."
But they said communication with the public is key, given that only half can currently identify the classic symptoms.
They concluded: "COVID-19 is associated with a wide range of symptoms. Many patients do not experience the UK’s official case-defining symptoms, initially, or ever, and other symptoms often manifest earlier.
"Limiting the symptomatic testing to those with these official symptoms will miss or delay identification of many Covid-19 cases, hampering efforts to interrupt transmission."
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