An error on the NHS Covid app failed to record thousands of potential exposures, leaving people potentially unaware that they needed to self-isolate, it has been revealed.
The issue stemmed from the app being unable to record whether people were close enough to each other to possibly transmit coronavirus.
‘Shockingly low’ numbers
The NHS Covid app launched in England on 24 September, and more than 19 million people have downloaded it.
The error was first revealed by The Sunday Times, which reported that the so-called “world beating” app had “systematically failed to send alerts telling people to self-isolate after they came into contact with infected people.”
App users who had a high enough risk score to trigger an alert were not contacted. A government source allegedly told the Sunday Times that the numbers of users being sent warning since the app launch were “shockingly low.”
The technology was designed to recognise people as having been in close enough proximity for a transmission. Instead, the error meant that they were recorded as too far away for the virus to be passed between them.
The problem took five weeks to fix, with a voluntary software update available last Thursday (29 Oct). Android devices were among the worst affected.
The error was first admitted to in a blog post last week, confirming that, although the developers were aware of the risk threshold needing to be lower than the original design, it had not been updated ahead of the national release.
The NHS Covid app has suffered numerous problems since it’s launch in September. With 19 million people using the app, officials have refused to reveal data on how many people have been told to self isolate through it.
An urgent fix on the app was needed just two days after its launch date, when it was revealed that 61,000 NHS tests could not be linked to it.
The app was also updated in October, to stop users from receiving ‘phantom’ alerts, informing them they had possible Covid exposure, but with no follow up alert afterwards.
A health department spokesman said, “The NHS Covid-19 app is the only app in the world using the latest Google/Apple technology to better gauge distance to identify those most at risk, and is deemed ‘excellent’ by international standards.
“As previously published, we anticipate more app users who are at high risk of having caught the virus will receive a notification to self-isolate, and that will be to everyone's long term benefit by reducing the chances of those with the virus passing it on to others."