NICOLA Sturgeon has warned Scots that covering their faces will not make them immune to coronavirus.

The Scottish Government has advised people to wear a cloth face covering - such as a scarf or bandana - if they are in enclosed spaces, like shops or public transport, where it could be difficult to stay away two metres from other people.

When questioned on the evidence behind the change in guidance, she stressed people must not think covering their faces will give them "some kind of invincibility" from Covid-19.

Speaking at First Minister's Questions in the Scottish Parliament, Sturgeon said: "Anecdotally, I see it, I'm sure all of us are seeing it, many people are choosing to do this anyway.

"And a concern I have is that people are thinking it gives more protection than it actually does and people have some kind of invincibility if they are covering their face to being infected with this virus.

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"The rationale for the guidance is to set out what the limited benefit may be but also to say 'look this is not a substitute for the other things people should be doing'."

A face covering should be an "added precaution" people can take, she said, as she stressed the "most important things" were for people to stick to the existing rules on staying at home and frequent handwashing.

She was questioned on the issue by Scottish Tory leader Jackson Carlaw, who told her clarity had to be "one of the absolute priorities in terms of tackling Covid-19".

He told the First Minister: "We haven't been told exactly what the evidence is the First Minister has been using to inform today's change in advice."

Sturgeon said she had seen advice from Sage - the UK Government's Scientific Advisory Group for Emergencies - and had also discussed the issue with chief medical officer, Dr Gregor Smith.

She told MSPs: "One of the reasons I thought it was important to give guidance was yes, to say to people that there is now evidence - and the evidence is not overwhelming - but there is evidence I have seen that there could be some benefit in a situation where somebody has the virus but is asymptomatic and maybe shedding that virus but doesn't know they have it, that that may give some additional protection against them transmitting the virus to others.

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"Given there is that indication of some benefit there I think it is important people know that."

The First Minister added: "The rationale for the guidance is to set out what the limited benefit maybe but also to say 'look this is not a substitute for the other things people should be doing'.

"Effectively the advice is if you are leaving your own home to go into an enclosed space where you will be with other people and it will be difficult to keep the recommended two metres social distancing, those are the circumstances in which you should wear a face covering - and I stress face covering and not medical mask.

"The circumstances in which people should be in these situations right now should be very limited, if you are following the stay at home guidance.

"The examples we have given today are people going to essential work on public transport and people going to a supermarket for food shopping, or perhaps a smaller shop where social distancing is more difficult."