The UK government will appeal to Britons’ sense of civic responsibility to encourage use of the new NHS contact-tracing app, despite an admission from its developer that it “might not work” when first rolled out.
The app forms part of the UK’s Test, Track and Trace strategy, which is being piloted this week on the Isle of Wight to assess whether expanded testing and the tracing of virus infection between people can help contain the disease.
Other countries such as Singapore and South Korea have already launched similar digital tracing systems, which have been used together with manual contact-tracing by public health officials to identify and isolate rapidly those who are at risk as lockdown restrictions are lifted.
Matt Hancock, health secretary, said he had a “simple message” for Britons as he unveiled the new technology on Monday. “By downloading the app, you’re protecting your own health, you’re protecting the health of your loved ones and the health of your community,” he said.
Mr Hancock added that the new system was a “huge national undertaking” that was “unprecedented” in scale and complexity.
“The aim of test, track and trace is to hunt down and isolate the virus, so it’s unable to reproduce,” he said, adding that it “allows us to take a more targeted approach to lockdown, while still safely containing the disease”.
Once downloaded, the UK app will use low-energy Bluetooth signals to build up a log of app users who have been in proximity to one another. If one of these people develops a fever or cough, they can notify the app, which will in turn alert recent contacts that they may be at risk of infection. The suspected Covid-sufferer can request a test, and their contacts will be updated on their risk level depending on the result.
Matthew Gould, chief executive of NHSX — the digital arm of the National Health Service, which has developed the technology — cautioned that the app was “not a silver bullet or a standalone solution” but would work together with other public health measures, including virus-mapping efforts by an army of 18,000 manual contact tracers.
He also conceded that given the rapid development of the app, “some things might not work” at first. “This is new technology,” he told reporters. “There will inevitably be unintended consequences. When we launch it, it won’t be perfect — it will definitely evolve.”
One of the controversies of the UK design is that NHSX has chosen not to use a template provided by Apple and Google which stores most of its data on individual phone handsets, rather than a single database. While Germany and Italy have decided to adopt this template, both Britain and France favour a more centralised system — separate to the Apple and Google model — which gather anonymised “identifiers” for each app user together on a government server.
Mr Gould sought to counter concerns from privacy campaigners that central databases risk compromising security. “As we have developed the app, we’ve put privacy right at the heart of it and the way it works,” he said. “It doesn’t know who you are, it doesn’t know who you’ve been near, it doesn’t know where you’ve been.”
The app asks for the first half of its users’ postcodes, which covers between 8,000 and 12,000 households, depending on location. This information is not uploaded on to the system until users become symptomatic and notify the app. In future, the NHS may request more data from users, including age and gender details.
Experts from the National Cyber Security Centre, a branch of the UK signals intelligence agency GCHQ, have worked with NHSX to design a central database that is rigorously anonymised and protected from hackers. The app assigns each user a numerical code which is kept separate from personal data. “We cannot link your app identity to anything that has your name or NHS ID on it . . . With the data that’s on the app, you cannot go back and identify a person in any way we can conceive,” a security official explained. All data will be hosted within the UK.
One limitation of the Isle of Wight trial happening this week is that residents will still be in lockdown, so they are unlikely to come into contact with many other people outside their households. But Mr Hancock said once this first trial of the app had been completed, a national rollout could start from mid-May.
Whether or not the app is successful will depend largely on uptake. Fewer than a fifth of Singaporeans downloaded the app developed by their health authorities, but epidemiologists in the UK have calculated that about 60 per cent of Britons would need to engage with the app for the best chance of slowing the spread of the virus.
Jonathan Van-Tam, deputy chief medical officer for England, admitted there were “uncertainties” about uptake and that a “significant proportion” of the population would need to use it. “This would [give us] additional oomph in the contact tracing space, which in turn will give us additional room to manoeuvre in terms of other social distancing easing that we can consider in the weeks and months to come,” he said.
