A contact tracing phone app that could help ease the UK out of COVID-19 lockdown is to be trialled on the Isle of Wight this week.
The CV19 app, developed by NHSX, the digital arm of the health service, aims to track people who become infected with SARS-CoV-2 and alert others who they have been in close contact with.
The app uses Bluetooth technology to register contact when people come within 2 metres of each other for at least 15 minutes.
If a user develops COVID-19 symptoms, they use the app to alert an NHS central database which can forward an alert to other users who have come into contact with the individual.
It is understood that the Isle of Wight was selected for the trial because any infections can be more easily traced among a smaller population contained in a limited space.
The app was previously trialled at an RAF base in North Yorkshire.
UK Adopts a Centralised Approach to Contact Tracing
The technology has triggered concerns about privacy and the security of data held centrally. However, there have been suggestions that its use could allow some areas of the country to come out of lockdown earlier than others.
The development of CV19 represents a decision by the UK to 'go it alone' with its own technology.
Last month, the Government rejected a model jointly proposed by Apple and Google to launch their own contact tracing app.
The system being developed by the two tech giants also uses Bluetooth to log distances between the phones of individuals but takes a decentralised approach in which tracking and alerting takes place between smartphones.
The German Government recently abandoned plans for a centralised technology approach in favour of the Apple-Google model.
An editorial last week in the journal Nature highlighted that despite the pandemic's global nature there was no international consensus for how apps should operate. It raised concerns that citizens were being asked to give up their personal data despite "scant published evidence on how effective these apps will be at either identifying infected people who have not been tested or, if widely used, stopping the spread of the disease".
Expert Briefing on the Technology
Prof Jonathan Van-Tam, England's deputy chief medical officer, was among a group of experts who briefed journalists earlier at the Science Media Centre. He declared himself very supportive of the centralised approach "because of the massive anonymised data set that can be subject to AI techniques and machine learning", which would contribute to understanding of the disease.
As the country passed the peak of cases and moved towards the next phase, hopes were being pinned on the app to supplement traditional contact tracing.
"I think we've reached a point of our understanding now where it's highly unlikely that the COVID-19 virus is going to go away; very likely that we are going to have to live with this virus in our communities to a greater or lesser extent until we find long-term solutions such as effective vaccines," he said. "And therefore contact testing and contact tracing is going to have to become part of our daily lives for the future."
Mathew Gould, chief executive of NHSX, said privacy had been built into the system, and anyone downloading it would not have to part with personal details.
"It doesn't know who you are, it doesn't know who you've been near, it doesn't know where you've been," he explained at the briefing.
Instead each phone with the app installed would be assigned randomised identifiers. "Your Bluetooth will remember the randomised identifiers of who you've been near, who also has the app, how long you've been near to them for, and how close you were."
Those details remained on the individual's phone until symptoms developed and details were voluntarily uploaded by the user to the NHS.
But even when the information was passed on "we still don't know who they refer to", he added.
Downloading and using the app would be voluntary, and people would be able to delete it from their phones at any time, he said.
How Many People Need to Use the App?
Questions have been asked about what proportion of the British public might be willing or able to download and use the app.
A recent study by the University of Oxford's Nuffield Department of Medicine said that the epidemic could be suppressed if 80% of all smartphone users used the app, or 56% of the population overall.
Michael Gove, minister for the Cabinet Office, told Sunday's daily Downing Street briefing that the app would be "one arrow in the quiver" and that "the more people who download the app the better".
Grant Shapps, the transport secretary, told Sky News it would amount to a "huge national effort". He acknowledged that not everybody owned a smartphone, and that some people might not download it. "We need, for this to work, 50, 60% of people to be using this app", he said.
An Australian tracing app, COVIDSafe, which allows State and Territory health officials to contact users if they have been in close contact with someone who has tested positive for the virus, was downloaded three million times in the 3 days since it was launched in a population of around 25 million.
A week later, it had only achieved a reach of four million.
However, Mathew Gould said that even a low download figure for the UK version would be "fantastically valuable" and would "speed up contact tracing".
The Government has already announced it intends to recruit 18,000 coronavirus contact tracers by the middle of this month.
Dave Stewart, Isle of Wight council leader, told the Island Echo: "The opportunity to be part of this initial roll-out and lead the way for the rest of the nation is consistent with the council’s prime objective of securing the best possible protection for our whole community from COVID-19."
However, Prof John Newton, director of health improvement at Public Health England, dismissed rumours that the trial might bring an early easing of lockdown measures for the islanders.
"For the Isle of Wight, all the same safeguards apply," he told today's briefing. "So, the use of the app, and the contact tracing which we're also introducing in the Isle of Wight … are all there to give additional protection and safety," he said.
