Jon Crowcroft was one of the people developers for NHSX – the technology unit responsible for the Government’s now-abandoned in-house tracing app – who was approached for advice in February this year as they started to build a product.
Prof Crowcroft and a multi-skilled team won a grant from the Medical Research Council to build the app, which became one of the first to prove bluetooth technology could be used to track disease spread and provide otherwise unavailable data to authorities.
The UK Government made a U-turn on using its own NSHX-developed software last week, in favour of Apple-Google application programming interface, or API, now being rolled out by countries around the globe.
A UK Covid tracing app is now not expected until autumn at the earliest.
Prof Crowcroft, who is currently working on a future immunity passport design with the Bill and Melinda Gates Foundation, told the Standard the “major plus point” for the Apple-Google option will be its impact on travel as countries open up before a vaccine is found.
He said: “If they have the same form of app being deployed in the Republic, it will make that travel easy. The same for going to France – having the same model will help us travel across borders again. Even if the app is slightly less accurate, it will inter-operate.
“What would happen is if you are on the Eurostar to Paris and you sit next to someone who tests positive [for Covid-19] the next day, you would get a notification – even if you are on a UK phone – saying ‘you were next to X’.”
But the professor called for caution before becoming too optimistic, saying that even experts “don’t know how well” the tech giant API is going to work – and said in its current form it “may actually be worse” than the NHSX app.
He said: “I think the reason there has been a U-turn was not just technical. The way it was working in the Isle of Wight was actually pretty okay. We don’t even know how well the alternative is going to work. It has only been running in Germany since Monday, and we have no idea if it will be better or worse – it may actually be worse.”
Prof Crowcroft explained that any app would currently be responsible for tracing only around 20 per cent of cases, compared to 80 per cent by manual contact tracers – but that it will be crucial in advance of any second wave in the autumn.
He said: “If we get a second wave in the autumn or winter the app will be much more of a big deal because we will have many more cases.”
The expert explained that under the best case scenario, in the UK around 60 per cent of the population would download the app as only 80 per cent have a smartphone, and not everyone will access it. The app is also unable to work in all environments, and is therefore “only part of the system” and “all useless without testing in place”.
Some countries are abandoning the idea of an app altogether due to issues with bluetooth tech. Singapore is now not using any version and instead giving citizens a bluetooth wristband.
The Google-Apple API does not give central authorities in countries any information about who is contacted for self-isolation, or where the incidents or outbreaks are taking place.
Prof Crowcroft warned its downside compared to the originally planned NHSX in-house app will be that UK scientists will be unable to make important long-term findings. These would include more evidence to help determine how fast immunity wears off, and how many people asymptomatically carry the disease but remain infectious.
The Department of Health has said it will share progress made in the Isle of Wight pilot with Google and Apple – and Prof Crowcroft believes it should go further and publish the findings.
He said: “The Apple-Google combined design for this bluetooth low energy radio is not as sophisticated as the NHS one. It was done to get a general system that works on all phones and hasn’t had any opportunity to be optimised.
“What has happened is that the NHS spent a lot of effort in the Isle of Wight over the last month tuning how the bluetooth proximity technology works, and I know the guy doing it and he’s very, very smart. A lot of work went into that which has not yet gone into the Apple Google API Germany and other countries are starting to use.
“They don’t have that sophistication in there. It can be added, and what I really hope is that if the NHS publish what they have got from the Isle of Wight, how they created the proximity algorithm, then that will be a contribution to the whole world.
“NHSX will be able to say ‘hey, this wasn’t pointless, it can actually be added in to what Apple and Google provide’, and then all the other apps can benefit in improving accuracy.”
The expert said people in the industry are “positive this can happen”.
In a joint statement last week, Baroness Dido Harding, Executive Chair of NHS Test and Trace and Matthew Gould, CEO, NHSX, said: “Our response to this virus has and will continue to be as part of an international effort. That is why as part of a collaborative approach we have agreed to share our own innovative work on estimating distance between app users with Google and Apple, work that we hope will benefit others, while using their solution to address some of the specific technical challenges identified through our rigorous testing.
“We will also draw on the invaluable insight from all of those who trialled the app on the Isle of Wight – and the brilliant teams who have worked on it to date – to build an app that can form part of the end-to-end NHS Test and Trace service, and this insight will be integral to the next phase of development.”
Health and Social Care Secretary Matt Hancock, who has not confirmed the exact date an app will be released in the UK, said last week: “Countries across the globe have faced challenges in developing an app which gets all of these elements right, but through ongoing international collaboration we hope to learn, improve and find a solution which will strengthen our global response to this virus.”