Covid-19: App to track close contacts is launched in England and Wales

The government is urging all adults in England and Wales to download the NHS covid-19 smartphone app as an additional way of tackling the spread of the virus.

However, experts have questioned how useful it will be, given that the overall test and trace system is still struggling to meet the demand and to provide quick results.

Latest official data show that in the week up to 16 September the results of just 28% of swab tests were received within 24 hours, down from a third the week before.1 Only 77.7% of the close contacts of people transferred to NHS Track and Trace were reached (83.8% the previous week), and of these 74.7% were asked to self-isolate.

The app for England and Wales uses a smartphone’s Bluetooth technology to log the amount of time a person spends near other app users, records the distance between them, and alerts users when they have been close to people who later test positive for covid-19. The app will trigger advice to self-isolate if users have been in close contact with a confirmed case and also enables them to check symptoms, book a test if needed, and get their results (box 1).

The launch of the app brings England and Wales into line with Scotland and Northern Ireland, which already have similar apps operating.

The government said that the app protected the user’s privacy, generating a random ID for an individual’s device and not holding personal information such as name, address, or date of birth. No personal data are shared with the government or the NHS.

The NHS Test and Trace team behind the app has worked closely with giant tech companies, including Google and Apple, after what were described as “successful” trials on the Isle of Wight and in east London that helped fine tune the new version.

The government has been criticised by health experts such as the charity the Health Foundation for so far failing to publish the results of pilots,2 although a spokesperson for the Department of Health and Social Services for England told The BMJ that during the trial 350 000 people downloaded the app and 67 495 activated it with unique codes. The government said it would publish a full evaluation of the trial in due course.

England’s health and social care secretary, Matt Hancock, said, “We are at a tipping point in our efforts to control the spread of this virus. With infection rates rising we must use every tool at our disposal to prevent transmission, including the latest technology.

“We have worked extensively with tech companies, international partners, and privacy and medical experts—and learnt from the trials—to develop an app that is secure and simple to use and will help keep our country safe.”

Simon Thompson, managing director of the NHS covid-19 app, said. “This new version is so much more than just a contact tracing app. It has a range of features that will quickly alert you if you’re at risk of coronavirus [infection]. The more people who use it, the better it works.”

The BMA said the app should allow more cases to be identified but that it needed to complement a properly functioning test and trace system.

Lilian Edwards, professor of law, innovation, and society at Newcastle University and an expert on internet law and artificial intelligence, told The BMJ, “The usefulness of the app is completely tied to getting testing and return on tests fixed. Unless you can get testing and return on testing down to about three days, then the app isn’t going to do anything useful. It’s not a magic bullet.

“A drawback to the app is whether enough people download it to get coverage. Originally they were saying it wouldn’t really do anything unless you had something like 70% or 80% of the population downloading, but they seem to have changed their mind on that now and believe it can be useful however many people download it.”