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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 13 hours later)
Millions of people in the UK will soon be asked to monitor their movements, to limit the spread of coronavirus. Millions of people in the UK will soon be asked to download a smartphone app, which will monitor who they've been near.
The trial of a "test, track and trace" programme started on the Isle of Wight in early May. All 80,000 households on the island were asked to download a smartphone app designed to quickly trace recent contacts of anyone with the virus. It's part of a contact tracing programme to combat coronavirus.
Within a week, the app had been downloaded about 55,000 times. It has had mixed fortunes so far, but if it's judged successful, a nationwide programme will be rolled out within weeks. Health Secretary Matt Hancock says 21,000 contact tracers have now been employed, including 7,500 healthcare professionals.
What is contact tracing?What is contact tracing?
Contact tracing is used to slow down the spread of infectious outbreaks. Contact tracing is a system used to slow the spread of infectious diseases like coronavirus. It's already being used in other countries including Hong Kong, Singapore and Germany.
When someone gets coronavirus, everyone they have been in prolonged contact with will be tracked down and potentially asked to self-isolate. One method is for someone who's been infected to list all the people they've recently been in prolonged contact with.
Phoning or emailing the friends and family of coronavirus patients is one way of contact tracing Those people will then be tracked down by phone or email, and potentially asked to self-isolate,
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. Another way of tracing is by using a location-tracking mobile app, which identifies people the patient has been in contact with.
Contact tracing is already being used by various countries, including Hong Kong, Singapore and Germany. The advantage of the app is it can identify people the patient may not know - like fellow passengers on a bus.
The UK is planning to roll out its contact tracing app and phone team by the middle of May. 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 government originally said it wanted to deploy a contact tracing team of 3,000 civil servants and health workers, and 15,000 call handlers. It has posted several job adverts for people who are unemployed and keen to help handle the calls, subject to a two week training programme. Health Secretary Matt Hancock says 21,000 contact tracers have been hired, including 7,500 healthcare professionals.
Their telephone tracing will be used alongside the smartphone app. They will gather contacts from patients and trace those people by phone or email.
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. A free NHS app will also track when users come into contact with each other. 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 users with whom they recently had significant contact, potentially asking those people 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.
Why was the Isle of Wight chosen for the trial? Testing the testers
Mr 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. A trial programme is under way on the Isle of Wight, and if this is judged successful, a national programme will follow.
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. 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.
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.
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.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 and mass testing. There was manual monitoring of credit card transactions, CCTV and mobile phone tracking to piece together where people had been.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.
The UK probably won't use that level of tracking but a widely used app would allow the government to ease some restrictions. The UK probably won't use that level of tracking but a widely used app might help.
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. 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.
By comparison, about 67% of UK smartphone users have downloaded messaging app WhatsApp. 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.
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.
What if I don't have a smartphone?What if I don't have a smartphone?
Only people with a smartphone can access the app. As it launched the Isle of Wight trial, the government said there would be an option for people to report symptoms and order tests in other ways, including 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 reports falling ill, including app users, will be asked to record recent contacts either online or via telephone - so the hope is that tracers can reach all those at possible risk, not just people with the app. Everyone who displays symptoms will be asked to record recent contacts online or via telephone so tracers can reach all those potentially at risk.
One idea is that 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 says the government must take the risks seriously - 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, 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.
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.
Mr Hancock said the app will take "full consideration" of privacy concerns.