NHSX on track for May launch of Covid-19 contact-tracing app but challenges remain

The UK government's Covid-19 contact-tracing app remains on schedule for launch in May despite ongoing privacy concerns and only recently passing through alpha testing, leading UK scientists told MPs.

Giving evidence to the House of Commons Science and Technology Committee, as part of an inquiry into UK science, research and technology capability during the coronavirus outbreak, experts also admitted that it would be difficult to achieve the volume of users necessary to make the app’s use worthwhile. In addition, privacy and functional elements of the app were challenged by MPs.

The NHS digital innovation unit, NHSX, last week (24 April) revealed details of the eagerly awaited app, which is being developed by epidemiologists, mathematical modellers and ethicists at Oxford University’s Nuffield Departments of Medicine and Population Health. The app aims to automate the “laborious” process of contact tracing to help reduce transmission of the coronavirus by alerting people who may have been exposed, so they can take action to protect themselves.

Once installed, the app will start logging the distance between a user’s smartphone and other phones nearby that also have the app installed, by using Bluetooth signals. If a user becomes unwell with symptoms of Covid-19, they can allow the app to inform the NHS which, subject to sophisticated risk analysis, will trigger an anonymous alert to those other app users with whom the infected user came into significant contact over the previous few days. The app will suggest what action to take if anyone affected has been close to someone who has become symptomatic – including advising to self-isolate if necessary.

The app was recently alpha-tested at an RAF airbase in Yorkshire and will go through to a beta testing phase before launch, scheduled for May. NHSX chief executive Matthew Gould told MPs that the roadmap for the app’s development was as expected and that if there were no technology hitches it would be ready for launch by the NHS, according to the wishes of the UK government.

“I would expect it technically to be ready for wider deployment in two to three weeks. Whether it is then deployed depends on the wider strategy,”  he said.

The app has attracted questions and some criticism around its effectiveness in the battle against Covid-19 and whether it would protect user privacy. UK research body the Ada Lovelace Institute said it has seen no evidence to support the immediate deployment of digital contact tracing or immunity certification, while the NHS has already been involved in a dispute with Apple and Google over the IT companies’ own contact-tracing technology. NHSX accepts that the app could only make a positive contribution if installed by a large proportion of the population who trusted the app and followed the advice provided.

Gould said that users of the app could be confident that their personal data will be safe as the app has a series of protections built in. His message was reinforced by solicitor general Michael Ellis, who in answering MPs’ questions said: “Data on the app will not be held any longer than is absolutely necessary, and civil liberties and the privacy of information are absolutely crucial to the development of the app. We want people to trust it and to use it. It is going to be important to protect the NHS and to save lives - so every single mechanism we have will be utilised to protect the privacy of data.”

NHSX has chosen to take a centralised approach to storing data collected by the app, unlike other countries including Germany that are taking the decentralised approach recommended by Apple and Google for data protection.

Regardless of privacy issues, Gould acknowledged that it would be tough to reach the levels of uptake for the app sufficient to make its usage worthwhile. Professor Christophe Fraser, senior group leader in pathogen dynamics at the University of Oxford Big Data Institute, told MPs that around 60% of the UK population would need to use the app to help combat the spread of Covid-19. Fraser stressed that this would mean people using the app in the manner it which it was intended, rather than simply downloading it and self-isolating if  symptoms emerged.