A Digital COVID-19 Vaccine Passport System Is Still Premature

Questions of equity, access, and privacy demand answers before a vaccine passport will work.

As COVID-19 vaccines become more widely available, a growing number of corporations and countries have begun to consider requiring vaccine passports—proof of vaccination for “entry”—acting on the belief that those who have been vaccinated should be given some level of priority in living a normal life again. Although this system sounds promising in theory, numerous legal, ethical, and operational questions must be resolved before making vaccine passports a routine aspect of travel.

The appeal of a vaccine record verification system is compelling at least in theory as it could quickly and verifiably check a person’s vaccination status. The digital vaccine passport would be accessed using a smartphone application that links the user’s COVID-19 vaccination record to a QR code displayed on the device. In fact, the Biden Administration has already requested government agencies “assess the feasibility” of an electronic system that links coronavirus vaccine certifications to other vaccination documents.

If designed appropriately, a digital vaccine passport system could confer all the advantages of paper vaccination records plus benefits of technological efficiency and ease of use. Creating this system would require data sharing by health care providers, methods for verifying vaccine records, and regulation of how entities may request proof of vaccination. Employers may also mandate vaccination if, as part of their employment qualification standard, it is “a requirement that an individual shall not pose a direct threat to the health or safety of individuals in the workplace” and the employer demonstrates this threat cannot be “eliminated or reduced by reasonable accommodation” without vaccination. Employers may request proof of vaccination under the U.S. Equal Employment Opportunity Commission, so long as employees are not asked to answer pre-vaccination screening questions that may inadvertently disclose their sensitive health information.

To avoid accusations of discrimination, governments would need a strong enough justification in protecting public health to exclude unvaccinated Americans from particular places or activities.

Critics say the creation of a vaccine passport system could lead to a “two-tiered society,” exacerbating inequalities between vaccinated and unvaccinated populations. Right now vaccines are not equally accessible to all. Many states report, for example, that wealthier and whiter populations are getting vaccinated at much higher rates than low-income communities and people of color. Furthermore, systemic inequities in health care access pre-Covid have no doubt fueled vaccine hesitancy during the pandemic, particularly among certain ethnic and religious groups, minority communities, and people with disabilities. Requiring digital vaccination passports for entry to public and private places of business is likely to heighten these inequities.

The digital technologies powering such passports also raise privacy concerns. First, vaccination programs would require a substantial collection of health data. According to a 2019 report from the Centers for Disease Control and Prevention, only an estimated 60 percent of all adults 19-years-old and over participate in online immunization information systems. Broader utilization of such systems would be essential for facilitating the data sharing required to make vaccine passports effective. Second, any application must be interoperable, meaning it must work with multiple systems across organizational and technical boundaries. Also, unlike the yellow fever vaccination cards developed by the government, digital vaccine passports are largely being designed by tech companies and non-profits.

Whenever health information connected to an identifiable individual is stored, developers will need to develop safeguards for ensuring the security of that data. These safeguards include collecting only the minimum data necessary to render the app functional, storing data for as little time as possible, promptly deleting data after functional use, and avoiding any undisclosed third-party tracking.

Some researchers suggest that a vaccination passport could exist without sharing any personally identifiable or health information using new privacy-preserving techniques and encryption. But with non-governmental actors in control of the data, ensuring strong internal controls and safeguards becomes essential.

Emerging survey results from studies probing public acceptance of immunity or vaccination passports in the U.S. and U.K. yield mixed results. One study found that 48 percent of Americans favor “private certificates” compared to nearly 43 percent who support “government passports,” showing a slight preference for private administration over government administration. In another ongoing study of 3,500 respondents across seven European countries, researchers found that approximately 60 percent would support carrying immunity passports for themselves. Older respondents were generally more favorable, and those with lower perceived risks of being infected as well as greater trust in the government were positively associated with support for immunity passports.

Although the World Health Organization (WHO) has issued an interim position on vaccine passports, the Royal Society has proposed criteria to evaluate their use. Essentially, a passport should meet the benchmarks for COVID-19 immunity, with certification being linked to actual protection or limited transmission of the virus. The certification should also accommodate the differences in vaccine efficacy, as well as their efficacy against the variants that currently exist.

But until rigorous evidence demonstrates how effectively vaccines prevent transmission and for how long, there is a limit to how useful any vaccine passport can be for public health—especially if approved vaccines prove less protective against emerging variants. The study also recommends that passports be internationally standardized, possibly linked to the WHO’s Smart Vaccination Certificate. The study outlines other recommendations including ensuring that vaccine passports do not violate ethical standards or discrimination laws.

Reliable and accessible proof of vaccine-induced protection from COVID-19 could speed travel and economic reopening, but obstacles to wide-scale adoption of a vaccine passport system, as well as privacy and equity concerns, are so formidable that such a system seems premature.

Y. Tony Yang

Tony Yang is a professor and the executive director of the Center for Health Policy and Media Engagement at George Washington University.

Vasiliki Rahimzadeh

Vasiliki Rahimzadeh is a postdoctoral fellow with the Stanford Center for Biomedical Ethics at Stanford University.