Yesterday, Matt Hancock said that contact tracing teams would be part of a strategy that included the use of a phone app to identify recent contacts and warn them that they might need to self-isolate.
Is he putting too much faith in NHSX, a phone app to identify recent contacts and warn them that they might need to self-isolate, still being developed?
Experts widely report that 60% of the population would have to participate for such an app to be effective.
“If you ask me whether any Bluetooth contact tracing system deployed or under development, anywhere in the world, is ready to replace manual contact tracing [to deal with coronavirus], I will say … the answer is, no.” Those are not the words of a tech luddite but were posted by Jason Bay, head of digital services of the world’s most wired-up city state, Singapore. The island has seen only 10 deaths out of a population of 5.6 million and its response has been celebrated as a model approach to the virus. Singapore used large-scale testing of citizens and a digital app – TraceTogether – to track the spread of the Sars-Cov-2 infection.
But technology is no panacea to the crisis. With just 12% of Singaporeans using the app, Mr Bay correctly observes the quality of data analysis is only as good as the quality of the data provided. “False positives and false negatives have real-life (and death) consequences,” he writes. “We use TraceTogether to supplement (manual) contact tracing – not replace it.”
In the west the privacy challenges of smartphone apps are complex, and we must resist attempts to normalise any level of totalitarian surveillance. Yet the speed of the spread of the viral pathogen makes it difficult to see how such technology can be avoided. In such a system a person who develops symptoms and then, say, tests positive for Covid-19 lets his or her phone app know of their infection. This is then broadcast to every other app in the network which then searches their records to see if they have been close to the infected individual’s phone since the time of infection. For this to work in the UK an app must hold data temporarily and anonymously, be installed at users’ discretion, and have privacy at its core.
But this is only the first step. Until we develop a vaccine or a treatment, infections will have to be detected quickly, and infected individuals possibly quarantined. The bottom line is that to contain the epidemic and prevent another spike we will need an army of public health workers for ongoing testing and monitoring. How many would be needed? In Wuhan there were 81 public health officials for every 100,000 people. In New Zealand’s success story – just nine deaths in a country of 5 million people – the comparable figure was four. But those low staffing levels can be maintained because New Zealand had the outbreak under better control and the islands’ remoteness makes it easier to track visitors.
A study for Johns Hopkins university in the US suggests that with Covid-19 circulating widely for many weeks, and without sufficient levels of testing, a region might need 15-30 public health workers per 100,000 people to bring the crisis under control. In the UK that would mean a new coronavirus workforce of 10,000-20,000 people to work in a system that Conservative governments since 2010 have starved of cash. We cannot allow tech evangelism to obscure the need to start funding, finding and training workers so the country can be kept safe.