Devi Sridhar, professor of global public health at Edinburgh University, and a regular TV commentator on the coronavirus, told Holyrood’s Health and Sport Committee, that Mr Stewart “is absolutely right – covid passports are the way the world is going and Scotland needs to be ahead of this”.
Responding to a question from Mr Stewart, Professor Sridhar said: "Looking forward, everyone says, 'How are we going to get out of this?’
"I think if these vaccines stop transmission, which they look like they might, we will reach a stage of vaccine passports.
"It's already being discussed in the EU. We already have countries like Israel which have introduced green cards domestically if you’ve been vaccinated.
"And I think similar to yellow fever, where the The World Health Organisation (WHO) has certification if you've been vaccinated, we'll reach a stage where aviation will continue – and Spain and Greece are really keen on this for their tourism industries – where you will be allowed to fly and can have international mobility, but only when people are vaccinated and confirmation that you will not infect others when you travel."
Professor Sridhar added that WHO had not yet followed this pathway “because we do not know conclusively that vaccination status reduces your risk of transmitting to others”.
However, she said studies suggest vaccines reduce the chances of people becoming infectious.
She added: “This is really brilliant because that's the missing piece, in a way. I think once that's conclusive, they will move towards that."
She believes the next stage could be to introduce a vaccine passport system domestically.
She went on: “Then you can really start creating an incentive to people. You can say to them ‘if you want to go to the concert, if you want to be able to be active in the places where spreading occurs, then you have to protect and make sure you're not infecting others’.
"So, it's heading this way and Scotland needs to be ahead of this and preparing for it and thinking actually if we're going to do it, how do we do it properly."
Mr Stewart, speaking afterwards, said: “I have been repeatedly asking in the Scottish Parliament how do we make some inroads on the next few months on this? What I have observed is the EU is marching ahead of this.
“My own view is that I can only see the world’s economy and particularly tourism operating anything like normal if we have an internationally-recognised passport.
“I am very aware of data protection and individual liberties. This is obviously a difficult balance to strike but the main focus would be on access to travel and not to day-to-day services.”
He went on: “There seems to be a lack of willingness within the Scottish Government to have a proper debate. If there are already countries implementing Covid passports, our government is going to have to come up with some sort of system or we are at risk of being left behind.”