Dr Gregor Smith said some countries across Europe were seeing “exponential growth” in Covid cases, fuelled by both the so-called “Kent” variant – which is believed to be more transmissible and is now responsible for the vast majority of cases in Scotland – but also “variants of concern” from South Africa and Brazil.
"I spent a little bit of time last night looking at some of the data from different countries across Europe and there’s no doubt about it, there are many countries who are back into experiencing that exponential growth of the number of cases they are seeing,” Dr Smith said.
“Some of them some of the largest countries in Europe just now. They are experiencing that because they are now very exposed to three particular variants of concern which are seeding across Europe.”
Dr Smith said the B117 variant, which began in Kent in England, was “widely seeded” across the continent.
“We also have some countries in Europe just now, more worryingly, which are seeing growing cases of variants from South Africa and more recently the variant which came from Manaous in Brazil,” he said.
"The biggest concern that I have – are those two latter variants going to establish themselves in continental Europe as a potential source of problems?
"That worries me because of the rate of transmission associated with those virus, but also because of the potential they have for immune escape as well and we’re monitoring that situation very, very closely.
"That emphasises why it’s really important that we are taking all the safeguards we possibly can to limit the introduction of those back into our own country.”
Ms Sturgeon said she would speak to the aviation industry this week about when Scotland “might” see some element of international travel again.
She said: "I don’t think that will be possible before the 17 May, but my view is that it may not be possible for a period after that. I take no pleasure in saying that. All of us want to have every aspect of life back to normal.
"While we see lots of signs for hope here in Scotland and across the UK, the picture is not as rosy in many other parts of the world, including some other parts of Europe where we are starting to see some increase again in incidence of the virus.
"This is likely to be one of the restrictions that is in place for longer. This is just a hard fact. I wish it were different, but it’s not at the moment.”
Ms Sturgeon said she had tried “really hard” to get a four-nations approach to international travel, but pointed to England’s different approach to managed quarantine.
Travellers to Scotland have to stay in a quarantine hotel at a cost of £1,700 for ten days. However, in England, only people coming from countries on the ‘red list’ – where coronavirus cases are high – have to do so.