As the rollout of COVID-19 vaccines has progressed, countries have begun to look for ways to lift restrictive public health measures, like lockdowns. This has amplified the discussion around the effectiveness and potential challenges of vaccine certificates, or passports. Showing proof of vaccination record is not a new concept: from international travel to school enrollment, providing documentation of vaccination or immunity has long been used to prevent disease outbreaks and protect public health. However, despite the long history of vaccine or immunization certificates, COVID-19 vaccine passports are highly contested, with proponents seeing them as the only way to safely “go back to normal” and critics raising concerns about inequity, discrimination, and breach of privacy fears. Additionally, lack of international consensus on how or why vaccine passports should be used and differences in efficacy rates of authorized vaccines are likely to result in a patchwork of different compliance standards between countries for vaccine passports. This could in turn lead to conflicting information being given out to citizens on what vaccination requirements are necessary to comply with. In order for citizens to trust vaccine passports, countries need to be more transparent about how vaccine passports are used, their data security, as well as addressing vaccine inequity and potential discrimination that could result from them. Ensuring equitable enjoyment of the benefits associated with vaccine passports requires human rights considerations to be embedded in their design and implementation.

Vaccine passport proponents argue that vaccine passports and immunization certificates encourage people to get vaccinated and allow a gradual reopening of the economy, and the lifting of restrictive public health measures such as quarantines, business closures, and stay-at-home orders. Industries such as retail, travel, and entertainment particularly benefit from a mandatory vaccine passport scheme as they will be able to resume their commercial activities in a manner that protects both their customers and employees.

On the other hand, critics think that while vaccines remain scarce, vaccine passports would unfairly exclude individuals who cannot access the vaccine. WHO has advised against requiring proof of COVID-19 vaccination for international travel, and 70 countries have not yet begun their vaccine campaigns due to vaccine shortages. Requiring vaccine passports for  international travel would unfairly burden countries that lack adequate doses to fully vaccinate their population. Within a country’s borders, linking participation in social, civic, and economic activities to immunity passports would exacerbate existing inequalities and potentially result in adverse health outcomes, as individuals may voluntarily expose themselves to the virus in order to enjoy the social benefits of the vaccinated. Privacy issues have also been at the center of this debate as more countries consider the use of digital technologies in issuing vaccine passports, with some arguing that digitization will raise data protection liability and certificate falsification concerns and risks. Finally, the data still isn’t in on how effectively of vaccines reduce transmission, or the duration of their protection against COVID-19. Vaccine passports would have to incorporate this information as it becomes available.

Increasingly, countries have started planning ways to reopen their economies and allow for international travel. Many have started setting up standards for their own vaccine passport or certificate. Starting April 6, Iceland now exempts travelers with a certificate of vaccination from testing and quarantine upon arrival. Since then, no increase in COVID-19 cases has been recorded. Denmark has introduced the “coronapas” for those who have either been fully vaccinated, have recovered from COVID-19 in the past two to twelve weeks, or hold a negative test from the previous 72 hours. The is intended to allow non-essential businesses to reopen, with the country scheduled to be fully reopened on May 21. The pass does not currently facilitate travel outside of Denmark, but the government hopes it might eventually. At the regional level, the European Commission submitted a proposal to the European Parliament and the Council of Europe for a “digital green pass” that, if adopted, would restore free movement in the EU. This  has received pushback from individual member states, with concerns about data protection, discrimination, and the scientific importance of such a document. With near zero COVID-19 cases since June 2020, Australia and New Zealand have opted for an alternative approach, creating a travel bubble that allows for quarantine-free cross border travel for their residents. The efficacy of these approaches in reopening the economy and restoring cross-border travel while keeping COVID-19 transmission rates low remains to be seen.

Israel was among the first countries to introduce the vaccine passport. The Green Pass is an attempt to incentivize rather than mandate vaccination, and it seems to be working—a  recent study of 503 Israelis confirms that the benefits of a green pass would persuade a significant percentage of the population (31%) who were not planning on getting vaccinated anytime soon to get vaccinated.

The Green Pass, adopted in February, is available as an app or barcode printout, and is given to any individual vaccinated for COVID-19 as well as those who have recovered from coronavirus. Each group has a different limitation on the pass. Vaccinated people become eligible for its benefits the week after receiving their second dose, and the pass lasts for six months. For recovered COVID-19 patients, the pass is valid until June 30, 2021, regardless of infection date. To enter an establishment that complies with Green Pass requirements, the Green Pass and an identification document must be presented or scanned. The government keeps records of which businesses have implemented Green Pass requirements and provides this information to the public. The gyms, hotels, pools, cultural centers that were closed during the most recent lockdown are now open to those who have the Green Pass.

The Green Pass has raised concerns that certain individuals or communities will be left behind. Only in March did Israel offer the vaccine to Palestinians who work in Israel or in Israeli settlements in the West Bank, leaving 4.5 million Palestinians unvaccinated and without a green pass. The United Nations Human Rights office has called on Israel to ensure equal access to COVID-19 vaccines for Palestine. But the Israeli Minister of Health has said that Palestinians have oversight of their public health under the Oslo Accords, and the principle of self-determination. On March 21, the State of Palestine received 61,000 doses from a COVAX facility, with plans for additional vaccines to cover approximately 1 million people. Palestine has been able to source 10,000 doses of Russian-made Sputnik V vaccines, 2,000 of which have been sent to Gaza with an additional 20,000 Sputnik V doses donated by the UAE. Given that the Israeli regulators have not yet approved Sputnik V, it remains unclear whether Palestinians receiving this vaccine will be eligible for a green pass.

There are additional concerns around the functionality and privacy of the Green Pass app. The app has experienced serious problems since its launch with users finding its functionality slow and taking up large amounts of memory. Security experts who have examined the app have also found that the reliability of its verification of vaccination status is questionable.

In an effort to encourage those who are eligible to get vaccinated, the Israeli Knesset also passed a bill allowing the Israeli Ministry of Health to disclose information to local and national authorities on people who are eligible to receive the vaccine but have yet to do so. This law states that the information will be used solely for the purpose of encouraging people to get vaccinated and will be destroyed two months after the transfer of information. Despite assurances given by the chair of the Labor, Welfare and Health Committee, the fact that the local officials tracking who is unvaccinated will have access to personal identifiable data of users, such as ID numbers, addresses, vaccination dates or date of recovery from COVID-19, is highly concerning. Illegal data disclosures are also a major concern since the app uses an outdated encryption library that makes it vulnerable to security breaches.

Besides being a tool to open their economies, many countries—especially those whose economies rely on tourism—see vaccine passports as a way to restart international travel safely. Israel’s Green Pass has already proved valuable in opening up options to its vaccinated citizens for international travel. Israel and Greece entered into an agreement that allows vaccinated travelers to move freely between them. On March 23 Greece lifted a seven-day long quarantine requirement for all permanent residents of Israel, provided that they have been vaccinated against COVID-19 within 14 days prior to their arrival, can show proof of a negative PCR test, and hold a Green Pass certificate issued by the responsible public authorities. Starting March 31, Cyprus also recognized Israel’s Green Pass, exempting vaccinated travelers from Israel from the quarantine and the negative COVID-19 test requirements currently in place. The impact of this recognition scheme is not yet clear due to lack of travel data from Israel to Greece and Cyprus.

As vaccinations increase, governments will continue to weigh the benefits and drawbacks of vaccine passports. While seen as a way to incentivize vaccinations, vaccine passports raise ethical questions around vaccine equity and accessibility, even in countries where there is no shortage of vaccines. Incentivizing individuals to get inoculated as a way to gain access to an open economy still does not address the issue of vaccine hesitancy and misinformation that is working against the uptake of COVID-19 vaccines. Additional legal, scientific, and technical questions remain and any country utilizing vaccine passports should be fully transparent about the standard of implementation of the program, with a special focus on privacy protection. What works for one country may not for another and while we wait for international standards on vaccine passports, country-by-country implementation will result in a patchwork of what activities are acceptable to those fully vaccinated and those not, thus creating vaccine-stratified societies. The COVID-19 Law Lab will continue to track vaccination guidelines, exemptions, and passport programs for COVID-19 vaccines.

Anastasia Vernikou is a law fellow at the O’Neill Institute for National and Global Health Law.

Katherine Ginsbach M.S., J.D., is a law fellow at the O’Neill Institute for National and Global Health Law.