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Coronavirus: How does contact tracing work and is my data safe? Coronavirus: How does contact tracing work and is my data safe?
(about 4 hours later)
Everyone in the UK with a smartphone will soon be asked to download an app, which will monitor who they have been near. The UK will have a ''world-beating'' coronavirus tracing programme by 1 June, Prime Minister Boris Johnson says.
Originally due to be rolled out nationwide in mid-May, the government now says it will be ready ''in the coming weeks''. A team of 25,000 contact tracers will track down people who have been near those with coronavirus. Later on, an app will tell people if they have been near to someone with the disease and may need to self isolate.
The app is part of a wider contact tracing programme which will employ 25,000 people to track contacts over phone and email.
The prime minister says this team will be able to track the contacts of 10,000 coronavirus cases a day by 1 June.
What is contact tracing?What is contact tracing?
Contact tracing is a system used to slow the spread of infectious diseases like coronavirus. It's already being used in Hong Kong, Singapore and Germany. Contact tracing is a system used to slow the spread of infectious diseases like coronavirus. It has already been used in places like Hong Kong, Singapore and Germany.
One method is for someone who has been infected to list all the people with whom they've recently been in prolonged contact.One method is for someone who has been infected to list all the people with whom they've recently been in prolonged contact.
Those people will then be tracked down by phone or email, and potentially asked to self-isolate. Those people will then be tracked down and potentially asked to self-isolate.
Another way of tracing is by using a location-tracking mobile app, which identifies people with whom the patient has been in contact. Another way is by using a location-tracking mobile app, which monitors when users come into contact with each other.
The advantage of the app is that it can identify people the patient may not know - like fellow passengers on a bus. The advantage of an app is it can identify people the patient may not know - like fellow passengers on a bus.
However, it will only identify people if they also have the app.
What will contact tracing look like in the UK?What will contact tracing look like in the UK?
The PM says there is growing confidence that a ''world-beating'' a test, track and trace programme will be in place by 1 June. The government says a tracing system will be in place by 1 June, and that 24,000 contact tracers have already been recruited.
He added that 24,000 contact tracers had already been recruited.
They will gather contacts from patients and trace those people by phone or email.They will gather contacts from patients and trace those people by phone or email.
The free NHS app will also track when users come into contact with each other. It was meant to be rolled out in the middle of May but will also not be used widely until June. BBC political correspondent Ross Hawkins has seen a paper which says a trial will start with 10 councils across England, before being extended.
A free NHS smartphone app will work in tandem with manual tracing, which everyone with a smartphone will be asked to download.
It was originally due to be rolled out nationwide in mid-May, but the government now says it will be ready ''in the coming weeks''.
Once downloaded, it will run in the background of your phone, provided Bluetooth is switched on.Once downloaded, it will run in the background of your phone, provided Bluetooth is switched on.
If a user develops coronavirus symptoms, it is up to them to let the app inform the NHS.If a user develops coronavirus symptoms, it is up to them to let the app inform the NHS.
That message may trigger an anonymous alert to other users with whom they recently had significant contact, potentially asking them to go into quarantine or be tested.That message may trigger an anonymous alert to other users with whom they recently had significant contact, potentially asking them to go into quarantine or be tested.
Has the Isle of Wight trial been successful? Has the Isle of Wight app trial been successful?
A trial programme is under way on the Isle of Wight, and if this is judged successful, a national programme will follow. A trial of the tracing app is under way on the Isle of Wight.
Mr Hancock says the elderly population on the island - and lower number of smartphone users - made it a useful place to study the spread of a virus. Health Secretary Matt Hancock says the elderly population on the island - and lower number of smartphone users - made it a useful place to study the spread of a virus.
Relatively restricted travel to the island was also a factor.Relatively restricted travel to the island was also a factor.
As of 14 May, just over half of the island's 140,000 residents had downloaded the app.As of 14 May, just over half of the island's 140,000 residents had downloaded the app.
However, security flaws have been flagged in the app which researchers say pose risks to users' privacy, and could be used to prevent alerts being sent. However, security flaws have been flagged in the app. Researchers say these pose risks to users' privacy, and could be used to prevent alerts being sent.
GCHQ's National Cyber Security Centre has told the BBC it was already aware of most of the issues raised and is in the process of addressing them. How have other countries used contact tracing?
Contact tracing has been credited with helping to lift restrictions in other countries. A variety of methods have been used:
Will contact tracing help end lockdown?Will contact tracing help end lockdown?
Contact tracing has been credited with helping to lift restrictions in other countries, when combined with other measures. It is hoped that contact tracing combined with other measures could help ease lockdown restrictions.
South Korea never went into lockdown thanks to an early strategy of extensive tracing and mass testing. There was manual monitoring of credit card transactions, CCTV and mobile phone tracking to piece together where people had been. It is unlikely that the UK will ever have the same level of tracing as somewhere like South Korea.
The UK probably won't use that level of tracking but a widely-used app might help. A widely-used app might help, but take-up would have to be massive for the virus to be totally supressed. Academics advising the NHS estimate 80% of smartphone users - 60% of the population - would have to download and use it.
However, take-up would have to be massive for the virus to be totally supressed. Academics advising the NHS estimate 80% of smartphone users - 60% of the population - would have to download and use it. For comparison, the highly successful messaging app WhatsApp has only been downloaded by 67% of UK smartphone users.
For a sense of scale, it's worth considering that even a successful app such as WhatsApp has only been downloaded by 67% of UK smartphone users.
People would also have to be honest about displaying any potential symptoms, and inform the NHS.People would also have to be honest about displaying any potential symptoms, and inform the NHS.
What if I don't have a smartphone?What if I don't have a smartphone?
The app only works on smartphones. If you don't have one, you should be able to report symptoms and order tests over the phone and via an online service.The app only works on smartphones. If you don't have one, you should be able to report symptoms and order tests over the phone and via an online service.
Everyone who displays symptoms will be asked to record recent contacts online or via telephone so tracers can reach all those potentially at risk.Everyone who displays symptoms will be asked to record recent contacts online or via telephone so tracers can reach all those potentially at risk.
What can the government do with my data?What can the government do with my data?
Not everyone is happy with the government and third parties being given access to people's data. Civil rights group Liberty says the government must take the risks seriously - using the app should not be a condition to leaving the lockdown or returning to work. Not everyone is happy with the government and third parties having access to people's data. Civil rights group Liberty says using the app should not be a condition to leaving the lockdown or returning to work.
''Millions of us are going to need to trust the app and follow the advice it provides,'' says NHSX, the technology arm of the health service. It says the information gathered will only ever be used for health and research purposes. The NHS says information gathered will only ever be used for health and research purposes.
The UK app will use a "centralised model", meaning the matching process will take place on a computer server.The UK app will use a "centralised model", meaning the matching process will take place on a computer server.
An alternative, decentralised model was put forward by Apple and Google, where the exchange happens on people's handsets.An alternative, decentralised model was put forward by Apple and Google, where the exchange happens on people's handsets.
The tech giants say their version makes it harder for hackers or the authorities to use the computer server logs to track and identify specific individuals.The tech giants say their version makes it harder for hackers or the authorities to use the computer server logs to track and identify specific individuals.
But NHSX says its centralised system will help give it more insight into how the disease spreads. But NHSX, the part of the NHS developing the app, says its centralised system will help give it more insight into how the disease spreads.