The limitations of the popular Microsoft software likely caused the delays in processing data
Credit: Christian Dorn from Pixabay
The failure to enter the details of 16,000 coronavirus cases into the NHS Test and Trace system seems to have been caused by ill-advised use of Microsoft Excel software.
Between 25 September and 2 October, details of 15,841 people to have tested positive for coronavirus in the UK were not provided to the contact-tracing scheme as part of the daily data submission from Public Health England. These have since been belatedly added to the system, resulting in a big spike in daily cases reported on Saturday and Sunday.
Speaking in the House of Commons yesterday, health and social care secretary Matt Hancock said that the temporary loss of the data came as a result of a “specific issue [that] was in a PHE legacy computer system that we had already identified needed replacing”.
It is understood that details on coronavirus cases was received by PHE – as purely text data – in CSV file formats. This information was then transferred to Excel, which limits input to a little over a million rows of values.
If, as is reported by the BBC, PHE uses not just CSV, but also the 33-year-old XLS file format, the number of rows is limited to 65,000. With each case requiring multiple rows, the number of actual cases able to be entered into an XLS file could have been limited to several thousand – with any data beyond this that was provided to the government agency being cut off when it was entered into a spreadsheet to be passed on to the Test and Trace programme.
Even before the limitations of the current system caused the issue with the missing data, Hancock said that “I had already commissioned the replacement of it and that replacement is currently being built”.
“We knew that this was a system that needed replacing,” he added. “That work is underway, at the same time as the remedial action to sort the problem more immediately.”
With each confirmed case reporting an average of about four close contacts each, the delay in providing the data will likely mean that contact tracers were unable to get in touch with more than 60,000 people that might otherwise have been advised to self-isolate.
“The chief medical officer [Chris Whitty] has analysed the new data,” Hancock told the Commons. “The CMO’s advice is that the assessment of the disease and its impact have not substantially changed. That is because the just under 16,000 cases were essentially evenly spread, so it has not changed the shape of the epidemic. It has changed the level, in terms of where we are finding the epidemic and in what sorts of groups.”