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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 16 hours later)
Millions of people in the UK will soon be asked to track their movements to limit the spread of coronavirus. Millions in the UK will soon be asked to track their movements to limit the spread of coronavirus.
Health Secretary Matt Hancock has announced that the trial of a "test, track and trace" programme will start on the Isle of Wight on Tuesday. All residents will be asked to download an app. The trial of a "test, track and trace" programme is starting on the Isle of Wight. Residents will be asked to download a smartphone app designed to quickly trace recent contacts of anyone with the virus.
If it's successful, the programme will be rolled out to the rest of the UK. If it's successful, a nationwide programme will be rolled out within weeks.
What is contact tracing?What is contact tracing?
Contact tracing is a method used to slow down the spread of infectious outbreaks. It is commonly used in sexual health clinics, when infected patients are told to contact anyone with whom they have been intimate. Contact tracing is used to slow down the spread of infectious outbreaks.
In the coronavirus pandemic, it means tracking down anyone sufferers have been in prolonged contact with, to potentially ask them to self-isolate. When someone gets coronavirus everyone they have been in prolonged contact with will be tracked down and potentially asked to self-isolate.
This is often done through phone calls to the friends and family of coronavirus sufferers, complemented by an automated location-tracking mobile app. Phoning or emailing the friends and family of coronavirus patients is one way of contact tracing
Unlike tracing in sexual health clinics, it can be difficult to know who you've come into close enough contact with to spread coronavirus. And scientists don't entirely agree what "close contact" is. This can be combined with a location-tracking mobile app, to pick up others they have been in contact with, for example on public transport.
The World Health Organization recommends staying one metre apart, while the UK government recommends two. Its scientific advisers say two seconds spent one metre apart is as dangerous as spending one minute two metres apart. Contact tracing is already being used by various countries, including Hong Kong, Singapore and Germany.
Only distance will be captured by the app, so it will miss many of these key risk factors, like length of time spent in proximity with some and in what setting (inside or outside, well-ventilated or not).
These will have to be picked up in discussions with the "army" of contact tracers.
Contact tracing is already being used extensively by various countries, including Hong Kong, Singapore and Germany.
The UK is planning to roll out its contact tracing app and phone team by the middle of May.The UK is planning to roll out its contact tracing app and phone team by the middle of May.
What will contact tracing look like in the UK?What will contact tracing look like in the UK?
The 18,000-strong team will feature about 3,000 civil servants and health workers, and 15,000 call handlers. The government is getting ready to deploy a contact tracing team of 3,000 civil servants and health workers, and 15,000 call handlers.
This telephone system will be used in tandem with a tracing app, available to download on smartphones. Their telephone tracing will be used alongside the smartphone app.
Using Bluetooth, the free app tracks when its users come into contact with each other, automating the tracing process. If a user develops coronavirus symptoms, it is up to them to let the app inform the NHS. The free app tracks when users come into contact with each other.Once downloaded, the app runs in the background of your phone, provided Bluetooth is switched on.
Their disclosure may trigger an anonymous alert to users with whom they recently had significant contact, again potentially asking those people to go into quarantine or be tested. If a user develops coronavirus symptoms, it is up to them to let the app inform the NHS.
For those without smartphones, an alternative could be a Bluetooth-enabled wristband, like those being used in other countries to detect lockdown breaches. That message may trigger an anonymous alert to users with whom they recently had significant contact, potentially asking those people to go into quarantine or be tested.
Announcing details of the Isle of Wight trial, Health Secretary Matt Hancock said the programme will allow the government to take a "more targeted" approach to the lockdown while containing the virus.
The app will take "full consideration" of privacy concerns, Mr Hancock said.
Why was the Isle of Wight chosen for the trial?Why was the Isle of Wight chosen for the trial?
Mr Hancock says the elderly population on the island - and projected lower number of smartphone users - was a factor in choosing it. Health Secretary Matt Hancock says the elderly population on the island - and estimated lower number of smartphone users - was a factor. If it is successful despite these challenges then that will show it can work across the UK.
He says this means the trial will therefore address "as many of the challenges" as possible in rolling the app out nationwide.
John Newton, the UK government's testing co-ordinator, says that relatively restricted travel to the island makes it an "ideal place" to study the spread of a virus.John Newton, the UK government's testing co-ordinator, says that relatively restricted travel to the island makes it an "ideal place" to study the spread of a virus.
Will they 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.Contact tracing has been credited with helping to lift restrictions in other countries, when combined with other measures.
South Korea never went into lockdown thanks to an early strategy of extensive tracing, combined with mass testing. South Korea never went into lockdown thanks to an early strategy of extensive tracing and mass testing. There was monitoring of credit card transactions, CCTV and mobile phone tracking to piece together where people had been.
The nation not only asked citizens to recall their movements, it used credit card transactions, CCTV footage and mobile phone tracking to piece together where they had been. After a daily peak of 900 cases, it is now diagnosing just a handful of new daily cases. The UK probably won't use that level of tracking but a widely used app would allow the government to ease some restrictions.
If adopted widely enough, contact tracing might help ease UK restrictions, although it is unlikely citizens will be tracked to that extent. Take-up will have to be colossal for the virus to be totally supressed. Academics advising the NHS estimate 80% of smartphone users - 60% of the population - would have to actively use it.
The UK government first attempted contact tracing early on in the outbreak, before there were too many cases for it to be effective.
However, less movement under lockdown means new outbreaks should now be easier to track.
Phone tracing can be very labour intensive and time consuming, with tracers in Ireland reporting making about 40 phone calls per infected person.
The mobile app is easier, but take-up will have to be colossal for the virus to be totally supressed. Academics advising the NHS estimate 80% of smartphone users - 60% of the population - would have to actively use it.
By comparison, about 67% of UK smartphone users have downloaded messaging app WhatsApp.By comparison, about 67% of UK smartphone users have downloaded messaging app WhatsApp.
The academics' model does not take into account the over 70s, due to their average low smartphone usage, and the assumption many will be shielding and so not coming in to contact with lots of other people.
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.
Those without smartphones could end up wearing a Bluetooth-enabled wristband, like those used in other countries to detect lockdown breaches.
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 said the government must take the risks seriously, and should not make installing the app a condition to leaving the lockdown or returning to work.Not everyone is happy with the government and third parties being given access to people's data. Civil rights group Liberty said the government must take the risks seriously, and should not make installing the app 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 digital development arm of the health service. It says the information gathered will only ever be used for health and research purposes, and that the app can be deleted at any time. ''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, and that the app can be deleted at any time.
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 and help it to make the app more efficient.But NHSX says its centralised system will help give it more insight into how the disease spreads and help it to make the app more efficient.
Mr Hancock said the app will take "full consideration" of privacy concerns.