As Europe races to set up a digital health pass scheme to save the holiday season from the pandemic, technical and political obstacles are showing just how big a challenge the world faces in building such systems, people involved in the effort say.

Developers are grappling with issues ranging from the practical – such as what to accept as proof of being COVID-19 free – to the philosophical, including debates over discrimination and personal privacy.

Southern countries that depend on tourism like Spain, Greece and Portugal are clamoring for a quick rollout of the promised European Union “digital green pass,” saying their economies will not withstand the loss of another summer season.

The EU Commission plans to award a contract this month for a central system for verifying the digital passes, which will use QR codes that can be scanned into a smartphone app. It will also provide a template to help member countries develop their own apps – though some have already readied their own versions.

The gateway is supposed to launch in June after testing in May. But the bloc’s less tourism-reliant northern states warn launching a viable solution so quickly will be a stretch, especially given the number of stakeholders in the 27-nation bloc.

“It’s an aggressive timeline and it requires cooperation,” said Mats Snall, the head of Sweden’s digital vaccine passport initiative.

Bugs to Fix

The list of unresolved issues in the vaccine passport scheme is long.

There is still no consensus on whether antibody tests provide sufficient proof that a person who has recovered from COVID-19 is immune, sources involved in the efforts say.

Adapting the scheme for overseas visitors represents a challenge too, after Commission President Ursula von der Leyen told the New York Times on Sunday that the EU would open its doors to vaccinated Americans this summer.

Member states also worry about the security of personal information, though the Commission has promised the online certificates will contain minimal data: name, date of birth, the specific health information, its date of issue and a unique identifier code.

And while vaccine passports have not become a political football to the extent they have in the United States – where right-wing politicians denounce the idea as an impingement on personal freedom – concerns about digital tracking loom large.

The data put into the digital certificates will be easily amenable to forgeries, cautioned Michael Veale, who lectures on digital rights and regulation at University College London.

At the same time, training and equipping staff across Europe to verify the certificates could well prove to be impossible in practice, creating a form of “security theater” that is more intrusive than useful in practice, added Veale.

Trial Underway

The wrangling over vaccine passports resembles last year’s debates over contact-tracing apps, which some experts thought could help stem the pandemic but mostly foundered in the face of technical bickering, lack of uptake, and huge waves of infection that rendered them mostly moot.

But vaccine passports are inherently simpler: unlike contact-tracing apps, they don’t need to communicate with other phones, or track movements in any way.

Instead, a digital health pass, issued by a doctor or health center, would feature a QR code containing pre-authenticated information that attests a traveler has been vaccinated against COVID-19 or has received a negative PCR test result.

EU member states are creating apps for individuals to upload the QR code into their smartphones. Officials would be issued with separate checking apps: a ‘green’ result would mean the certificate is valid, ‘red’ would be invalid.

The EU gateway would assure that, say, the German app could easily be read in Portugal.

Estonia, which already tested a digital immunity passport for workplaces last year, is considered in Brussels to be the most advanced in building its own national app, but others aren’t far behind.

France has just added a feature to its existing coronavirus contact-tracing app, allowing users to upload recent test results and proof of vaccination. It is trialing the app initially on airline flights to Corsica.

Germany is starting by creating a standalone app to provide proof of vaccination, but plans to then incorporate the digital certificate via a wallet feature into the Corona-Warn-App, launched last year to enable contact tracing, sources say.

Spain is one of the digital green pass’s most vocal advocates, hailing it as a safe way of facilitating mobility having lost over 80% of its foreign visitors in 2020, a 51-year low.

“Spain cannot afford another summer like 2020,” a source at the tourism ministry said. “Port and airport authorities have already contracted the services needed to implement and recognize the digital certificate.”

(Additional reporting by Supantha Mukherjee, Foo Yun Chee and Douglas Busvine.)