Detailed work is underway examining a 'circuit breaker' lockdown in this month's school holidays if Covid-19 cases continue to surge, the Deputy First Minister has confirmed as Scotland recorded its highest death toll since June.
John Swinney said no final decision had been made on a short-term nationwide shutdown, which would see curfews and restrictions on activities for at least a fortnight and probably longer.
But he told a Holyrood committee that officials were conducting "detailed work" on the proposal, which could be implemented to coincide with this month's school holidays.
He said such "interruptive action to try and slow further and more aggressively" target the virus may be required if it "continues to grow at an accelerated rate."
Jason Leitch, Scotland's national clinical director, said the move would help suppress the virus temporarily but warned there could be major implications for the economy, society and schools.
776,959 people in Scotland have been tested for #coronavirus— Scottish Government (@scotgov) September 30, 2020
The total confirmed as positive has risen by 640 to 29,244
Sadly 7 more patients who tested positive have died (2,519 in total)
Latest update ➡️ https://t.co/bZPbrCoQux
Health advice ➡️ https://t.co/l7rqArB6Qu pic.twitter.com/Xde6WUwnCw
Their interventions came as Nicola Sturgeon announced 640 more cases and seven deaths had been recorded, the highest daily death total since June 17.
She also disclosed there were 94 Covid admissions to hospital in the week ending Sept 26, an increase of 60 per cent compared to the previous week.
But she insisted a rapid rise in hospitalisations and deaths, as experienced during the first wave of the virus, was "not inevitable" if Scots adhere to her rules.
In a rallying call to Scots to "stick with the restrictions", she suggested that university clusters are hiking the case numbers but there was a "very strong view" among her advisers that stopping different households meeting would work.
Ms Sturgeon said the restrictions she announced last week, including a 10pm hospitality curfew and ban on indoor visits to other households, should start driving down the figures "a month from now or thereabouts."
This was echoed by Boris Johnson at a Downing Street press conference, when he said the measures he unveiled for England would "take time to feed through." However, he said he would "not hesitate" to impose further restrictions if needed.
Prof Chris Whitty, England's chief medical officer, said numbers in hospital are heading in "the wrong direction" and warned: "We have got a long winter ahead of us."
He highlighted charts showing a north-south divide in England, with the North East, North West and Yorkshire experiencing a "significant rise" in test positivity.
A Scottish Government document leaked last week showed that ministers were considering a return to the restrictions imposed in late March, when people could leave home only for essential shopping, work for key workers, and one daily exercise session.
The document also suggested travel restrictions and closing hospitality venues for two weeks in an effort to break the chain of transmission.
Mr Swinney told Holyrood's education committee that "some form of circuit breaker" had been suggested by the UK Government's Scientific Advisory Group for Emergencies (Sage) but there was no "specific proposition" about the form it should take.
The Education Secretary said: "The suggestion has been made, the elements and the circumstances are being explored, but it would be dependent on two fundamental elements being made more certain.
"One was whether there was a necessity for such an interruptive action of that type, and secondly some detailed work, which is being considered, on what that might involve."
But he said that "frankly, the last thing I want to have to do is to close schools" as there was "very little evidence" of transmission in classrooms.
Appearing alongside Mr Swinney, Prof Leitch said: "Some modellers suggest you should do it repeatedly, so you would do two weeks, open for a period, then two weeks again, but that has implications for the economy, implications for society, implications for schools.
"So it is a very difficult balance about whether we think this new iconic measure would be something we would recommend for Scotland."
He said the real answer to tackling the virus was "whole population measures all the time until we get science to get us out the other end." However, he added: "A circuit breaker would just be a help on the way potentially."
Speaking later at her daily briefing, Ms Sturgeon said the latest daily death toll was a “very sharp reminder” of the danger the virus presented.
Although Scotland has recorded a record number of daily cases over the past week, she said lower testing in spring meant that figures in March and April had shown “a much smaller tip of a much bigger iceberg”
But she said: "As night follows day, if we allow infections to continue to rise, they will go from younger people to older people, people in older, vulnerable groups will get sick, be admitted to hospital and intensive care and die.
"And that's the path this virus will take if we won't get in its way and interrupt it."