The trade union said the push for testing will be its urgent priority over the next 48 hours as the number of workers in self-isolation increases.

The call came as it was reported that home visits to some of the most vulnerable were reduced as more than half of care workers required to self-isolate in Glasgow’s largest home care provider.

Roz Foyer, general secretary designate of the STUC, said: “We are only in the early weeks of this crisis and yet some of our most crucial public services, that lives literally depend on, are in danger of breaking down. Frontline staff are doing the right thing and following government guidance That is why it is imperative that testing for all essential frontline workers across Scotland’s public services and in our food stores are introduced immediately.

“We risk a situation in which infected essential workers without symptoms are working, whilst conversely, others are unnecessarily self-isolating.

“The number of firefighters in Scotland have been cut over recent years. For the period of the crisis, firefighters are undertaking a range of services we wouldn’t normally expect them to do, but must also maintain staffing levels to cover for emergencies.

“Meanwhile strain on the care system, even before the coronavirus hit, is a matter of public record with staff struggling to deliver 15-minute care visits and often forced to work split shifts.

“We wrote to the Scottish Government on Friday asking for this matter to be urgently addressed and will be pressing for delivery on this when we have a cabinet level meeting with the government early (this) week.”

• Read all of our articles relating to COVID-19 here.