UK collaborates with Google, Apple on contact tracing App

By Dr. Liji Thomas, MDApr 14 2020

The UK Health Secretary Matt Hancock recently announced that the UK government’s National Health Service (NHS) is planning to release an app that will alert people who have been in the proximity of a self-reported symptomatic individual – via anonymous phone-to-phone alerts.

Hancock said all data would be handled according to the highest ethical and security standards, and would only be used for NHS care and research. “If you become unwell with the symptoms of coronavirus, you can securely tell this new NHS app," he explained. "And the App will then send an alert anonymously to other app users that you've been in significant contact with over the past few days, even before you had symptoms so that they know and can act accordingly… we won’t hold it [the data] any longer than is needed.”

Contact tracing in the COVID-19 pandemic. Image Credit: Bob Boz / Shutterstock B By

Why is contact tracing important?

Contact tracing, which involves tracking all individuals who have been in contact with a suspected or confirmed case, is a public health intervention that could play a huge part in mitigating the COVID-19 pandemic. It slows the virus spread by informing those who have been exposed and reminding them to self-isolate. This message is what the NHS app is designed to do.

Experts worldwide stress the importance of contact tracing, and governments are listening: Singapore released a contact-tracing app called TraceTogether in March. Now the UK looks to be next.

How does the app work?

The system is relatively simple: if you feel unwell, you enter your symptoms into the App. Local health agencies then test you, and if you test positive for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2),  you use the App to find out who’s been close to you. The App then alerts these people that they have been close to someone infected, without the possibility of them identifying you from the message. The identity of the infected individuals is never publicly released: it’s stored in an encrypted code that’s only accessible to public healthcare organizations.

Apple and Google, two of the biggest phone manufacturers in the world, have teamed up to create the backend application program interface, or API, for the App. Their technology uses Bluetooth wireless radio signals called digital identifiers (which are both anonymous and change frequently) to communicate between phones, identifying who’s been close enough to be at risk. Apple and Google have been developing the software for almost three weeks now, and hope to release it for government use in May.

Ultimately, they plan to incorporate the App into iOS and Android operating systems. This will allow a more significant percentage of the general population to have access to the alert system. Such an expansion of use could potentially have a huge impact: iOS and Android are the systems that run practically all the smartphones in the world.

The collaborating companies are planning to extend this software to governments first, and then integrate the software into their respective operating systems in the coming months. Google plans to do this via its ubiquitous Play Store system.

Tracing contacts without betraying the identity

One of the most important things about the NHS app is that it doesn’t track the user’s absolute location, as some other methods do. Instead, it measures the phone’s proximity to other phones. This does not guarantee absolute privacy, but it is a step up from location-tracking software like those based on GPS.
A significant [and obvious] requirement of this technology is that a large number of people use them. Many worry that the government may make the use of this system mandatory. However, both Apple and Google insist that they won’t allow their technology to be used in this manner. Anyone who doesn’t want to participate can delete the App, and they won’t track them, says an Apple representative.

The major weaknesses of this approach

Unless a large percentage of people opt in to use this App, it will not succeed in tracing contacts well enough to be of use. Experts worry that without government directives, voluntary participation will be too low to be of benefit.

A government may require the use of its own public server to participate, which will hinder participation by those who habitually distrust the authorities.

Bluetooth signals are also sometimes liable to be inaccurate or to falsely identify someone in proximity when the individual is 6 feet or more away.

Counter-arguments to public data collection

Everyone is not convinced that this is in the best interest of public privacy, though. Professor Ross Anderson of Cambridge University says, "I recognize the overwhelming force of the public-health arguments for a centralized system, but I also have 25 years' experience of the NHS being incompetent at developing systems and repeatedly breaking their privacy promises when they do manage to collect some data of value to somebody else."

A former head of MI5 Lord Evans of Weardale worries that this “could be a real intrusion into people’s private lives.”

“This needs to be properly debated, it needs to be open in the way it is debated, there needs to be rules, and there needs to be redress if something goes wrong,” Lord Evans added. “We’re only going to get public support if we have those criteria met.”

However, in a joint statement by both software giants, they said, “Through close cooperation and collaboration with developers, governments, and public health providers, we hope to harness the power of technology to help countries around the world slow the spread of COVID‑19 and accelerate the return of everyday life.”