Delayed coronavirus app is ‘not core’ to contact-tracing programme, Lords told

In the context of the coronavirus pandemic, contact tracing involves identifying the recent contacts of a person carrying the virus, so those who may have been exposed can take appropriate precautions - in the case of Covid-19, this means going into quarantine for 14 days.

The programme was launched in late May, but at this time only involves manual contact tracing with no smartphone-driven, app-based contact tracing yet available.

A contact-tracing app which uses Bluetooth to detect contacts and shares data with a central server was recently scrapped, in part due to technical complications. Although a more privacy-focused version of the app is under development – utilising the Exposure Notification API collaboratively developed by Apple and Google for these purposes – the UK government has been downplaying the significance of the app for several weeks, despite originally insisting that the app would be central to its approach.

Key figures leading NHS Test and Trace today affirmed that the app is now considered to be only a peripheral part of the overall programme, in an appearance before the House of Lords Science and Technology Select Committee.

Dido Harding, who is heading the programme, said that Test and Trace had been promising so far. She said that in the first month of its operation, 73.9 per cent of people who had tested positive had been successfully reached by contact tracers and 86.5 per cent of the contacts they provided had also been reached.

Harding acknowledged that a contact-tracing app had many advantages, such as making it far easier to identify contacts whom people do not know personally (e.g. fellow commuters). However, she echoed the government line that such an app would not now be core to the Test and Trace programme.

“I think what we are building is a digitally assisted human service, rather than it is going to be purely digital,” she said, later adding: “The digital element is important, but actually it is not the core; the core is the scale testing platform, the scale tracing, the experts on the ground in local communities with our clinical contact tracing teams nationally. The app can then accelerate, but if you don’t have that core first, the app won’t work.”

Harding emphasised the government line that the public prefers to hear from human contact tracers and are therefore more likely to be willing to go into quarantine for two weeks after being notified that they may have been exposed. She said that it was necessary to maintain a human touch, including in the phrasing of alert messages.

Simon Thompson, MD for the contact-tracing app, said that the app would need good reliability around distance and time measurement in order to produce reliable risk scores and that he has “growing confidence” that the NHS will eventually be able to present an app good enough to earn public trust.

While he said that he was “optimistic” about progress on the app, he repeatedly declined to give any estimate for a launch date.

“We really recognise that the introduction of the app is urgent and important, but it must be a product that users can trust,” he said. Harding also declined to give any indication about when the app would be ready.

Neither Thompson nor Harding ruled out the possibility that the app may still not be ready before a potential “second wave” of infections later this year.