Downloading a solution
The questions that still remain
The NHS’ long-awaited contact-tracing app for England and Wales is finally available to download. But with the release of the app come a series of questions about its functionality, as well as a more fundamental concern over whether digital contact tracing can really make a dent on stopping the spread of Covid. Here are five unanswered questions:
Will enough people download the app for it be effective?
Contact tracing apps only work when they reach a critical mass of the population. Researchers initially argued they needed to be on more than half of people’s smartphones in order to reduce the spread of coronavirus, but scientists have since calculated that if one in six people use the app it could help cut deaths.
Will contact tracers be able to reach older people who can’t access the app?
Anyone using an iPhone 6 or older iPhone won’t be able to use the app, meaning it will be vital for telephone call contact tracing to continue its work.
Is the app going to mistakenly tell people to self isolate because of false positives?
Apple and Google’s contact tracing system allows governments to fine tune how their app works, adjusting the time and closeness of a “contact” before it registers in the database. NHS employees believe they’ve tuned the app to remove false positives by measuring when the potential coronavirus carrier was at their most contagious, according to BBC News, but we’ll only be able to tell over time whether the app avoids this.
Will people remember to scan QR codes?
A major function of the NHS app is scanning QR codes on official printed posters in restaurants and bars to help tracing efforts. But there are concerns that these posters won’t work well if people fail to scan them. Several residents of Newham, where the app was tested, said they were confused by the posters.
Can contact tracing actually stop the spread of coronavirus?
Governments and technology businesses around the world have invested millions into building this software, but we don’t yet have conclusive proof that the apps are effective in firstly tracking the virus and then helping people isolate. Matthew Green, a cryptographer at Johns Hopkins University, told Nature that “this could all turn out to be garbage. None of it could work. We have to try.” James Cook