Coronavirus - a new reality
The First Minister says measures brought in to tackle the spread of coronavirus will "change life as we know it''.
Nicola Sturgeon is advising people showing symptoms of Covid-19 - namely a persistent cough or a fever - to self-isolate for 14 days, along with every member of their household.
Ms Sturgeon also advised people to increase their efforts to "socially distance'', by refraining from going to places with a high concentration of people such as pubs or cinemas.
The measures come as the number of confirmed cases in Scotland increased by 18, to 171.
The First Minister said: "What we are asking people now to do will significantly and substantially change life as we know it for a considerable period of time.
"We are all in this together. If we do the right things, if we all follow the advice that is being given we can get through this and we will get through this.''
The First Minister echoed measures announced by Prime Minister Boris Johnson following a Cobra meeting on Monday with the four devolved administrations, who outlined plans to follow Scotland's lead and advise against mass gatherings.
She urged people to begin working at home where possible and asked that they stop going to places with a high concentration of people such as pubs or cinemas.
"Reduce all non-essential social contact, and do that as much as possible'', the First Minister said.
She added: "From today, that's advice that's being given to everyone in our population.''
The First Minister said social distancing is being recommended particularly for those who are over 70, have a medical condition that requires them to get the flu vaccination and pregnant women.
Ms Sturgeon also stressed that the measures were being brought in to "save lives''.
She said: "Let me stress very clearly that the measures we're announcing today are designed to reduce the peak impact of this outbreak and to protect the most vulnerable, to save lives and reduce the number of people who will die from it.
"But there will still be significant pressure on our health service in the months to come and it is vital that we continue with the steps that we're taking to increase that capacity as much as possible.''
Chief medical officer Dr Catherine Calderwood said Scotland was "on the cusp of a rapid acceleration'' in the number of cases.
She added: "We have in Scotland sustained evidence of community transmission of the virus here.
"The measures that we are outlining are to prevent the spread of this virus and to protect our whole population.''
She said it is aimed at preventing NHS services from becoming overwhelmed.
Most of those who contract the virus are expected to have either mild or moderate symptoms, the briefing heard, but Dr Calderwood warned that "some of our Scottish population will become very severely ill and sadly some may die''.
Very vulnerable people with compromised immune systems - estimated to be around 200,000 in Scotland - will be asked to self-isolate for a "period of weeks or months'', Dr Calderwood said.
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