Contact-tracing tech to be trialled on Isle of Wight from this week, amidst criticism that NHS’ ‘centralised’ approach risks privacy and effectiveness
The government has unveiled plans to begin testing the NHS’ coronavirus contact-tracing app on the Isle of Wight this week, as governments worldwide begin gradually easing lockdown conditions.
The app has been published to Apple and Google’s app stores, but is effectively hidden from the general public.
It is to be initially offered to NHS and council staff on Tuesday, ahead of a roll-out to the rest of the island on Thursday, health secretary Matt Hancock said in a briefing on Monday evening.
He said there was “huge enthusiasm” on the island for the trials, but others have raised concerns over the app’s privacy and effectiveness.
“Please download the app to protect the NHS and save lives,” Hancock told Isle of Wight residents in the briefing.
“By downloading the app, you’re protecting your own health, you’re protecting the health of your loved ones, and the health of the community.”
The app is intended to supplement the efforts of what Hancock called an “army” of human contact tracers.
When someone tests positive for Covid-19, human contact tracers look to track down whom the patient has been in contact with and isolate them.
The app, similarly, uses Bluetooth signals to detect and log other phones with a compatible app in the vicinity. When a person develops a confirmed case, the app alerts those who have come into contact with the individual.
But the NHS’ “centralised” approach has come under fire for exposing users to privacy risks and, as a result, potentially making people less willing to use the software.
The app processes anonymised data on a central server, allowing the NHS to track trends in the way the virus is spreading and to detect hotspots.
That approach contrasts to the “decentralised” approach adopted by many other countries, where all data processing is carried out on the devices themselves.
France and Japan are two notable exceptions, with both countries opting to employ centralised servers.
Apps using differing approaches may not be compatible, making it difficult to track contacts across borders.
The UK’s own Information Commissioner’s Office (ICO) has advised that “as a general rule, a decentralised approach” is more in line with the principle of organisations minimising the amount of personal data they collect.
The House of Commons’ human rights select committee also heard that the NHS’ approach involves privacy risks.
The NHS is planning to gradually allow users to opt into providing more location data, but law professor Orla Lynskey told the committee that such changes could become “very privacy invasive”.
Alan Davidson and Marshall Erwin of web browser maker Mozilla warned the centralised approach would “expand government access to the ‘social graph’” – data about users’ relationships with others.
“Regardless of the particulars, we know this social graph data is near impossible to truly anonymise,” they wrote in a blog post.
“It will provide information about you that is highly sensitive, and can easily be abused for a host of unintended purposes.”
Fears over privacy could mean fewer people install the app, making it less effective, but Matthew Gould, chief executive of NHS digital arm NHSX said the insights provided by a centralised approach outweigh such concerns.
“Even if the take up rate is 20 percent, that gives us important insights into how the virus is spreading,” he told the committee. “At 40 or 50 percent it will make a big difference.”
The government said it expects to have contact tracing measures in place by the middle of this month.
France, meanwhile, said its StopCovid contact-tracing app would enter testing in the week of 11 May, when the country takes the first steps to relax its lockdown.