The UK has confirmed plans for an app that will warn users if they have recently been in close proximity to someone suspected to have been infected by the coronavirus.

The health secretary Matt Hancock announced the move at the government's daily pandemic press briefing.He said the NHS was "working closely with the world's leading tech companies" on the initiative.

But one expert who has advised the effort has raised doubts about it.According to the BBC, NHSX - the health service's digital innovation unit - will test a pre-release version of the software with families at a secure location in the North of England next week.

Currently, the idea is that people who have self-diagnosed as having the virus will be able to declare their status in the app.

The software will then send the equivalent of a yellow alert to any other users who they have recently been close to for an extended period of time.

If a medical test confirms that the original user is indeed infected, then a stronger warning - effectively a red alert - will be sent instead, signalling that the other users should go into quarantine.

To report testing positive, the user would have to enter a verification code, which they would have received alongside their Covid-19 status.

Mr Hancock signalled that using the app would be voluntary, in the brief comments he made about it.

"If you become unwell with the symptoms of coronavirus, you can securely tell this new NHS app," he explained.

"And the app will then send an alert anonymously to other app users that you've been in significant contact with over the past few days, even before you had symptoms, so that they know and can act accordingly."

"All data will be handled according to the highest ethical and security standards, and would only be used for NHS care and research.

"And we won't hold it any longer than is needed."

A fortnight ago South Africa's Telkom, Samsung and the government teamed up to develop a track and trace database to identify the whereabouts of people who may have contracted coronavirus.

Telkom has been working with the National Institute for Communicable Diseases (NICD) and the Council for Scientific and Industrial Research (CSIR) to develop the database, which uses data from a person's phone to track where they have been.

Source: BBC