Proof-of-vaccination credentials for COVID-19 and considerations for future use of digital proof-of-immunization technologies: Results of an expert consultation.

Objective: As part of COVID-19 pandemic control efforts, digital proof-of-vaccination credentials were launched in Canada in 2021-2022 following widespread vaccine availability. Given the controversy over proof-of-vaccination credentials-often colloquially called vaccine or immunization "passports"-it is imperative to document successes, shortcomings, and recommendations for any future uses. Methods: This expert consultation applied inductive qualitative content analysis to online video interviews with key informants whose expertise ranged from ethics to public health to computer science to identify what we can learn from this experience with proof-of-vaccination credentials, and what decision-makers must keep in mind for possible future use of such technologies. Results: There remains a lack of consensus regarding appropriate language and scope for digital proof-of-vaccination technologies, the respective roles of the technology sector versus government in design and implementation, and parameters for future use. However, experts agree on many recommendations, including the importance of clear communication, evidence-based rationale for the use of proof-of-vaccination credentials, multidisciplinary consultation including academic experts and the public, and the importance of pan-Canadian standards for accessibility and interoperability. Identified risks of use that emerged, and should be minimized in the future, include risks of coercion and backlash; threats to access, equity and privacy; and impacts such as costs of the technology and workload burden of enforcement and fraud detection. Conclusions: There is much to learn from this first major use of digital proof-of-vaccination credentials. A full scientific review of the impacts on health and equity should be combined with expert recommendations to create pan-Canadian guidelines for the future use of digital proof-of-vaccination solutions.