The Unintended Consequences of Vaccine Passports

On Sunday, Health Secretary Sajid Javid stated in a BBC interview: “I am pleased to say that we will not be going ahead with plans for vaccine passports.” However, Number 10 has since clarified that vaccine passports are still a “first-line defence” against a winter wave of COVID-19.  

Whatever the Government’s true position – it seems to depend on exactly whom you’re talking to – introducing vaccine passports could have harmful unintended consequences, even aside from the threat they pose to civil liberties.

It’s now clear that, while the vaccines do provide strong protection against severe disease, their efficacy against infection is much more limited. In July, the Israeli Ministry of Health reported that the Pfizer vaccine’s effectiveness against infection had dropped to just 39%.

And an unpublished study by Qatari researchers found that the vaccine’s effectiveness against infection fell to zero after six months. (Though its effectiveness against severe, critical or fatal COVID-19 remained high for the study’s duration.)

The apparent decline in the Pfizer vaccine’s effectiveness may explain why Israel – which began vaccinating its citizens in late December – recently posted its largest daily total for the number of new infections since the pandemic began.

As many commentators have pointed out, the vaccines’ limited efficacy against infection rather undermines the case for vaccine passports. If vaccinated people are still capable of transmitting the virus, restricting attendance of large events to those who can show proof of vaccination is no guarantee of safety.

It would make more sense to create passports exclusively for those who’ve already been infected, since natural immunity seems to provide stronger protection against infection than the Pfizer vaccine. (I’m not seriously entertaining this proposal.)

The fact that vaccine passports wouldn’t have a large effect on spread isn’t the only problem. If implemented carelessly, they could actually lead to more COVID deaths.

How so? If vulnerable people (such as elderly persons for whom vaccines are less effective) are led to believe – wrongly – that the vaccines have strong efficacy against infection, they might take more risks than they otherwise would. For example, they might attend a large event, only to then become seriously ill with COVID-19.

Of course, the number of people in that category is likely to be small. But the hypothetical illustrates that vaccine passports aren’t simply a nuisance or a threat to civil liberties; they could even harm those they’re intended to help.

The small number of people still vulnerable to COVID-19 may need to continue taking precautions until more natural immunity is built up in the population. Vaccine passports will offer these people little protection in the meantime.