Vaccine passports are increasingly viewed as the route out of the coronavirus lockdown to a form of post-pandemic normality.
Advocates argue they would enable people who can prove they have had the jabbed to buy a drink, a cinema ticket or even a foreign holiday.
Companies could require new recruits to produce them before they can be hired, while countries could demand them in return for passing through their regular passport controls.
However, alarm bells are ringing among civil liberties groups over the implications of the new passports, which will not be in paper form but probably via an app demonstrating that the holder has been inoculated.
There are fears the move would create a vast digital ID system with sensitive medical records in the hands of Government officials as well as employers.
The problems of maintaining privacy in a database holding the vaccination details of more than 50 million British adults are obvious.
It would divide citizens into people who have been jabbed and those who have not, which the campaign group Big Brother Watch has argued could easily lead to a “health apartheid that’s incompatible with a free and democratic country”.
Ministers have also expressed fears that it could be “discriminatory” under current legislation for job offers to rely on proof of vaccination status.
Big Brother Watch’s director, Silkie Carlo, has said: “This dangerous plan would normalise identity checks, increase state control over law-abiding citizens and create a honeypot for cybercriminals.”
The hunt is on for a passport system which does not rely on a central database. One scheme being developed is for a person’s vaccination status to be registered and proved without disclosing their identity, relying on facial recognition to prove they have been vaccinated.