AN APP tracking people's coronavirus symptoms in their own homes has revealed that more than 6.6million people in the UK could have had the infection already.

The COVID Symptom Tracker, created by scientists at King's College London, was downloaded around 650,000 times in the first 24 hours after it launched on Tuesday.

By today it had been signed up to by 1.25million people and has become the third most popular download in the UK's App Store, with some 50,000 new users per hour.

Analysis of the first 650,000 users found that 10 per cent of them have had the symptoms of the coronavirus, which causes fever, coughing and tiredness.


Health authorities in the UK aren't testing anyone for the virus unless they're in hospital so the app could be one of the clearest pictures of how many people are ill.

If its infection rate of one in every 10 people is applied to the UK's population of 66million, that could mean 6.6m or more have already had the illness which has sent the world into hiding.

The early results from the app come amid a row in Britain over a lack of widespread testing and demand that NHS workers, at the least, are tested regularly to make sure they are safe to work.

Prime Minister Boris Johnson and his scientific advisers are adamant that widely available tests are on their way to the public once their accuracy has been tested.

"Our first analysis showed we're picking up roughly that one in 10 have the classical symptoms," app developer Professor Tim Spector told The Telegraph.

He said he believed there were 65,000 infected patients just among those who were using the app.

The official number of people with the disease in the UK is just 9,529, by comparison.

Tests are currently being rationed to hospital patients and those who become critically ill, so it is impossible to know the true scale of the infection.

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