The UK failed to add nearly 16,000 confirmed cases of coronavirus to its national track and trace system due to an Excel error. A number of reports, including from The Guardian, Sky News, and The Daily Mail, say the mistake was caused when an Excel spreadsheet used to track confirmed cases of the virus reached its maximum file size and failed to update.
The government agency that helps oversee the UK’s pandemic response, Public Health England (PHE), said some 15,841 cases had been left out of national totals because of the error but did not specify what caused the so-called glitch.
“Initial findings indicate that the issue was caused by the fact that some files containing positive test results exceeded their maximum file size, and they then failed to load into the central system because they couldn’t get through,” a spokesperson for PHE told BBC News journalist Leo Kelion. The spokesperson did not confirm or deny that Excel was involved.
The revelation caps a weekend of soaring coronavirus cases for the UK, which many have speculated could lead to a second national lockdown for the country: 12,782 new cases were announced on Saturday followed by 22,961 on Sunday.
The 15,841 “missing” cases made public today were originally recorded between September 25th and October 2nd. All those who tested positive for COVID-19 were notified by the UK’s health authorities, but the failure to upload these cases to the national database meant anyone who came into contact with these individuals was not informed. It’s an error that may have helped spread the virus further through the country as individuals exposed to the virus continued to act as normal.
According to reports from The Guardian and Sky News, the mistake was caused when PHE tried to collate data from multiple sources in the form of CSV files by loading them into Excel. This popular spreadsheet software has limits in how many rows it can load — 65,536 rows in older versions and 1,048,576 rows in more recent versions. Based on these reports, it’s not clear which version of Excel PHE is using, but the row-limit was reached regardless. As PHE workers tried to load more cases into the national database, they were rejected.
The solution, at least, is as simple as the error, and the overly large files have reportedly now been split into smaller batches. PHE didn’t confirm this but says the problem is now resolved, and that it passed the details of the backlog of confirmed cases onto the UK’s contact tracers as of 1PM local time on Saturday.
Update Monday October 5th, 4:37PM: The story and its headline has been to reflect the fact that multiple sources are now reporting the mistake was caused by an error involving Excel.