Mr Swinney said “something has clearly gone badly wrong” at the offices of private outsourcing firm Sitel, after concerns were raised about the lack of social distancing inside the call centre.
He revealed a total of 19 people had tested positive for Covid-19, including 14 staff members from Sitel and five other people “connected” to the call centre.
“There is a very serious situation in this facility, where something has clearly gone badly wrong in the working arrangements within the Sitel facility resulting in such an outbreak,” the SNP minister told BBC Radio Scotland.
Pubs, coffee shops and retailers linked to a coronavirus outbreak at an NHS test and trace call centre in Lanarkshire have been forced to close over fears the disease has spread more widely, the Scottish government has confirmed.
Deputy first minister John Swinney said five businesses had been shut for deep cleaning and staff advised to self-isolate after coming into contact with staff at the test and trace facility in Motherwell.
“We are putting in place all the test and protect arrangements so we can contain the outbreak as far as we possibly can do,” said Mr Swinney. “Some of those [five businesses] have been closed temporarily and deep cleaned, and members of staff at those premises advised to self-isolate.”
He added: “Essentially what we’re doing is extending the web from Sitel to establish who else might be affected by the outbreak.”
The Tavern bar on Motherwell’s Merry Street revealed on its Facebook page that it had closed to carry out deep cleaning after a part-time member of staff “was linked” to the outbreak at the Sitel call centre.
All 360 workers at the Sitel premises have now been tested, Mr Swinney said, with 307 results processed as of Tuesday night.
The deputy first minister said contact tracers have identified 63 people who had been in contact with the infected staff, adding that 56 of them had been reached and told to self-isolate.
NHS Lanarkshire and North Lanarkshire Council are both investigating the outbreak at the business park.
Labour MSP Monica Lennon said Sitel staff had told her they feared they were putting their health at risk because of the lack of social distancing arrangements in the office.
First minister Nicola Sturgeon said she was “concerned” about the claims, adding: “We all have to constantly remind ourselves of the importance of this in our own social interactions.”
She said the site on the outskirts of Motherwell was responsible for the large majority of the 22 coronavirus cases recorded in Scotland on Tuesday.