SCOTS who are tested for coronavirus in NHS labs should have their results back within 24 hours, Health Secretary Jeane Freeman has said.

She told MSPs "speed is of the essence" in the new test and protect strategy, which is due to begin this week.

Anyone who has Covid-19 symptoms is being asked to self-isolate and book a test, with contact-tracing carried out if they are positive.

Giving evidence to Holyrood's Health Committee on Wednesday, Freeman said guidance from the chief medical officer required that turnaround times for tests be 48 hours at the most.

MSPs were told the Scottish Government is aiming for a 24-hour target, which Scottish NHS labs are reaching but the UK Government's Lighthouse labs are taking longer.

READ MORE: Test and protect system to come into place this week

The Health Secretary said: "Our chief medical officer's office tells us that it needs to be within 48 hours to do the whole thing, what we're aiming for is a 24-hour turnaround.

"Because again, we're back to speed being of the essence. We don't control what the Lighthouse lab does but we can ask them to get to that point.

"That is what we're aiming for in all of our labs with consistency."

The committee also heard from Caroline Lamb, the civil servant who is director of the national test and protect portfolio.

Lamb said: "Within our NHS, Scottish-controlled labs, we are now consistently achieving or within 24-hour turnaround.

"In relation to the Lighthouse capacity, which for us is largely Glasgow, the most recent figures from the UK Government are that they're now achieving 89% turnaround within 48 hours with a strong commitment to improve that.

"The area where we have the most difficulty is in respect to the Milton Keynes Lighthouse, which is where the home testing kits currently go.

"We haven't yet got good data from the UK Government about turnaround times there and that is something we're raising with them."

Freeman also told MSPs that 1812 contact-tracers were in a "pool" ready to be used as the strategy is rolled out, though not all will be required immediately.

The latest studies estimate between 2.9% and 7.5% of the community has had Covid-19, she said.

Serology testing, which looks for antibodies to the virus, suggests between 3.4% and 13.6% of the population has these.

A trial is currently under way in the Lothians to see if saliva can be used to test for the virus instead of the more invasive method using swabs.

Discussions are also ongoing about opening up further testing sites including potential "high street based areas."

Conservative MSP Miles Briggs asked the Health Secretary about the policy to transfer untested hospital patients into care homes in the early days of the crisis.

Freeman said she "may have made different decisions" if she had the information then which she has now.

She added: "I didn't have hindsight then, Mr Briggs, I have it now. What I need to do now is make sure as I acquire the increased knowledge and understanding and changing advice...then I adapt what we're doing to incorporate that."