The CDC showed with its own numbers that the current variant infects vaccinated people, and vaccinated people “have measurable viral loads similar to those who are unvaccinated and infected with the variant.” Vaccinated people get and transmit the virus. Studies from Israel seem to suggest that those with natural immunity — having contracted and survived COVID — have more protection from serious illness than those who are vaccinated, especially those who were vaccinated early. Other studies from Israel show a waning effect of the vaccines.

These findings seriously complicate the medical rationale for segregating people based on their vaccination status alone. Australia’s government had hoped that a vaccine passport “would give us all confidence to actually engage in a lot of these broader activities that maybe we’re a little bit nervous about at the moment.” But arguably a person with natural immunity — even if unvaccinated — is safer to be around. If vaccinated people can become infected rather easily and spread just as widely, the vaccine passports don’t contain the spread. Vaccinated people will likely get less sick and overcrowd hospitals — though the waning effect of vaccination is worrisome on this note — but vaccinated people may go from their roped-off events and spread among the unvaccinated in other, less-restricted contexts.

And so the rationale for vaccine passports has to be bolstered with coercive or moral content. On the coercion side, a vaccine passport will simply hassle some undetermined number of people who aren’t particularly moved one way or the other about vaccines to go ahead and get them. The moral side is simply that after having lived through the miseries of this 18-month period, it would satisfy people to exclude or otherwise punish those who are lax about the vax.