Coronavirus: NHS contact tracing app to target 80% of smartphone users
A contact tracking app could help stop the coronavirus pandemic, but 80% of current smartphone owners would need to use it, experts say advising the SSN.
The Big Data Institute of the University of Oxford has modeled a city of one million people to simulate the impact of software.
If the spread is lower, academics say the app would still help slow Covid-19’s spread.
They add that allowing people to self-diagnose the disease could be crucial.
This means that users should only answer a questionnaire on the screen before they are judged to be at significant risk of infection. They shouldn’t have talked to a health advisor or waited for a medical test result.
This would send a series of warnings to the people they recently approached, suggesting that they return to self-isolation.
Experts say that “speed is essential” and that delaying the traceability of one-day contacts from the onset of symptoms could make the difference between epidemic control and rebirth.
“There would be more people receiving notifications following false warnings,” explained Prof. Christophe Fraser.
“But in reality, it translates into fewer days of self-isolation and quarantine, because the effect of suppressing the epidemic more quickly outweighs the risks of waiting for a test before being notified.”
Those over 70 were not taken into consideration, on the basis that they would remain “protected” by staying at home, he added.
University of Oxford academics are a mix of epidemiologists and ethics who recommend NHSX – the digital innovation unit of the health service – on what basis the contact tracking app should be created. They are not involved in coding or designing the software itself.
Their model takes into account the different age groups, home structures and movement patterns in an attempt to maximize the number of people who have been allowed to move freely once a contact tracking app has been launched.
“We are trying to introduce the app towards the end of the blockade,” added prof. Fraser.
“When you install it, it takes a few days to start logging data before it can be fully functional.”
The group first published a document on his work in late March.
Since then, they have changed their model to take account of changing factors, including the fact that Covid-19’s infection rate has been faster than expected.
They also changed plans from using a system that relied on GPS location readings and scanning QR codes to one that depends solely on Bluetooth signals. This was done to provide users with more privacy, which in turn could encourage adoption.
The hope is that the use of the app, as well as other measures such as hand washing and social distancing by vulnerable members of the population, will prevent a second spike in infections or the need for repeated national blockades.
The team estimates that 56% of the general population should use the app to stop the epidemic. Professor Fraser said it equates to 80% of all existing smartphone owners, based on Ofcom data.
“It’s a very ambitious goal,” acknowledged the professor.
“It’s not something that would typically happen for a new app, even an incredibly popular one, but if we can explain that it is a public health intervention, it will be new and different.
“Some of my colleagues have … commissioned major surveys in several European countries including the United Kingdom.
“Over 80% of the people surveyed said they would probably either install this app when it was explained in detail what it would do.”
Even if fewer people install the app, the team estimates that an infection will be avoided for every two users.
The Oxford team suggests that the use of the tool should be voluntary. However, this will present a challenge.
On March 20, Singapore became one of the first countries to deploy a voluntary contact tracking app, TraceTogether.
But only about 12% of the population installed it, and after a spike in new cases the city-state introduced a blockade on April 7, which it called a “switch.”
To complicate matters further, a small number of phones still in use in the UK do not support the required Bluetooth Low Energy system, making the target even more difficult to achieve.
Professor Fraser said officials were discussing giving smartphones to those who don’t – or cheaper and wearable Bluetooth devices – in order to increase the number of citizens involved.
NHSX also wants to keep the activation app.
But some have already begun to explore the implications that it becomes mandatory.
Lillian Edwards, Internet law expert, has drafted a law to safeguard citizens’ rights that says:
- any compulsion must be public, legitimate, necessary and proportionate to the public objective of defeating the coronavirus
- sharing data for purposes other than crown defeat must require users’ consent
- a new Commissioner responsible for safeguarding Coronavirus should act as a watchdog
Others – including the computer security expert Ross Anderson is Kai-fu Lee, AI entrepreneur – questioned whether contact tracking apps have any chance of success and fear that they may give “false hopes” to politicians seeking a way out of the blocks.