The global economy has been severely disrupted by Covid-19, with the virus wreaking particular devastation on the travel industry. While international travel will eventually return, either as governments start to bring infection rates under control or with the development of a vaccine, it’s a waiting game that many airlines, tour operators and hotels aren’t willing to play. In recent months, the idea of introducing digital immunity passports has begun to circulate as a potential lifeline to jumpstart international leisure travel.

“An immunity passport is a presentable proof of immunity to Covid-19,” said Husayn Kassai, co-founder and CEO of Onfido, a London-based technology company specialising in facial biometric certification. “It is designed to help an individual prove that they have been tested and that their test result belongs to them, but without having to share any personal information.”

Immunity passports are currently being examined primarily for the benefit of frontline medical workers, allowing them to continue working safely with reduced risk of an outbreak in hospitals.

An immunity passport is a presentable proof of immunity to Covid-19

In April, Onfido was invited to submit a proposal for digital health certificates to the UK Parliament’s Science and Technology Committee. In their proposal, Onfido casts immunity passports as “the linchpin of a new normality”. They would allow users to create a digital identity by uploading an official document (such as a passport or driver’s licence) along with a selfie taken on their phone, which would be verified using AI technology. The identity would then be paired with a certificate of immunity issued by a national health service. The end result would be a code on their phone that could be scanned to enter workplaces, public buildings or even airports. Onfido would provide the technology to verify users’ identities, but it would be up to the UK government to securely manage the health data and introduce a system of testing for immunity.

Consideration of immunity passports in the UK is still in its early stages, with the British government examining submissions from other facial recognition and identity firms, such as Yoti, Nomidio and Berlin-based IDnow, as well as a range of medical experts and academics on the viability of an immunity-based scheme. The jury is still out on whether the UK will formally adopt immunity passports, but the potential for such documents to accelerate reopening parts of public life has caused similar proposals to pop up in Germany, Indonesia, Italy, Israel, Colombia, Argentina, Estonia and the US.

Some of the earliest countries to be impacted by the virus have been quick to adopt health certificates, with China embracing the use of a health code app that shows whether a user is symptom-free in order to check into hotels or ride the subway, as reported by Reuters. While not officially an immunity passport, the Chilean government has begun issuing “virus-free” certificates to citizens who have recovered from Covid-19, allowing them to return to work without restriction of movement.

The ticket to reviving the travel industry?

Restoring travel is crucial for global economic recovery. According to the World Travel and Tourism Council, in 2019 tourism contributed nearly US$9 trillion to the world’s GDP and accounted for 330 million jobs – roughly one in 10 jobs around the world. However, for travel to fully recommence, governments will understandably require proof that people aren’t bringing Covid-19 with them. Presenting verified proof of immunity might become a requirement for passengers before airlines will allow them to board a flight, similar to a passport or visa.

John Holland-Kaye, CEO of the UK’s busiest airport, Heathrow, has welcomed the introduction of an internationally recognised immunity passport, while acknowledging the success of such a scheme would depend on other countries adopting similar systems. “If the UK government, with one of the biggest aviation sectors in the world, were to get together with the European Union and United States, between them they’d have the global diplomatic and economic power to set the international standard,” he told Sky News in May.

On a call with investors in April, CEO of Delta Air Lines, Ed Bastian said he would “make whatever changes to the business model that will be necessary”, including adopting immunity passports if required by the US government. Bastian pointed out how readily travellers adapted to new security regulations introduced by TSA and Home Security in the wake of the 9/11 terrorist attacks, and said the most important thing for travellers is confidence their safety is being well managed.

Health certificates are also beginning to be trialled by hotels. Sidehide, a contactless online reservations platform, announced in May it would partner with Onfido to deliver a contactless booking system using immunity passports. Users will be able to use a QR code to verify their immunity status and then book participating hotels directly through the app. Travellers check in on arrival via the app and can go straight to their room without any contact with hotel staff.

The problem with testing for immunity

Perhaps the biggest hurdle standing in the way of the introduction of immunity passports is the scientific knowledge about Covid-19 itself. It is still unclear exactly how accurate antibody tests are, and when antibodies are detected, how long they remain in someone’s body.

When the human body comes under attack from infection, our immune system’s response is to produce antibodies that help detect and destroy the virus. These antibodies can remain in our blood for a period of time after recovery to guard against repeat infections. Antibodies are one of the key defences against infection, which is why they have become a focal point for testing.

But for an immunity passport to work in practice, governments and health practitioners need reliable serology tests that can accurately identify antibodies in a person’s bloodstream, which the World Health Organisation says is not possible at this time. A scheme by Emirates to screen airline passengers for Covid-19 antibodies using rapid immunodiagnostic tests was withdrawn after an audit found only 30% of results were accurate. False results could lead to individuals being granted immunity status even if they have never contracted the virus.

The reason serology tests aren’t yet fully reliable is because Covid-19 is still new and researchers are working to better understand it. So far, the virus doesn’t seem to be playing by the rules when it comes to traditional immunity theory. Scientists have discovered patients who had recovered from infection, but mysteriously didn’t develop any antibodies. Historical blood samples have been found to contain traces of Covid-19 immunity cells that predate the discovery of Covid-19, suggesting some people had pre-existing levels of resistance before the virus was discovered in China in December 2019.

There is also growing doubt about how long people who have been infected with Covid-19 remain immune to the disease. There is some evidence to suggest that while antibodies can be detected in patients who have recovered from a severe case of Covid-19 for at least three months, a growing number of studies that show in milder cases the antibodies appear to rapidly decline from around three months after infection. Researchers at the University of California, Los Angeles, who conducted one study on antibody-longevity, urged caution over using antibodies as a basis for immunity passports. Another part of the immune system known as T-cells have shown more promise, however, as a longer-lasting source of immunity against Covid-19.

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A further complication is that in some cases Covid-19 patients have been shown to also carry and potentially spread the virus for up to three months after their recovery. In addition, the world’s first proven case of reinfection, with a different strain of Covid-19, has just been reported out of Hong Kong.

The sum total is that we are still grappling to understand the nature of immune responses to Covid-19 and it is too early to pin our hopes on serology testing. There are also concerns that immunity passports, which create a rubber stamp of approval, may mislead the public as to the complexity of their immune status, resulting in them ignoring public health advice and increasing the risk of continued transmission. It could also create a perverse incentive for individuals to seek out infection in order to gain immunity and return to “normal life”. In May, a poll by the Daily Mail found 19% of Britons would consider deliberately becoming infected if immunity passports were introduced by the UK Government.

If, or when, a Covid-19 vaccine is developed in the future, it is possible a vaccination certification scheme similar to that already used for yellow fever could be introduced to permit travel. However, most experts believe a vaccine could become widely available by mid-2021 – an agonising wait for the tourism sector – and even this is an optimistic prediction.

A slippery slope

Civil rights advocates on both sides of the Atlantic have flagged the introduction of immunity passports as the potential beginning of a slippery slope. At a time when Black Lives Matter has forced the world to critically examine its structural inequalities, these groups warn immunity passports could create a new privilege in the form of an antibody elite.

Combining health data with biometric data further increases the ability of states to build up highly detailed, intrusive and intimate records of people

The American Civil Liberties Union (ACLU) says immunity certificates could exacerbate existing racial disparities in the US. This is because the industries most likely to adopt them are those where employees cannot work from home – such as food production, sanitation, transportation and delivery. These industries typically employ immigrants, workers of colour and women: demographics who already experience unequal access to healthcare. These workers risk infection to earn a paycheque and have limited safety nets if they become ill. Workers who do survive infection and gain immunity could be given preference for work over others without immunity, creating a new underclass. These workers are confronted with a terrifying choice to either remain unemployed or take the risk and become infected.

If that sounds unbearably bleak, it has happened before. When yellow fever swept through 19th-Century New Orleans, workers who weren’t immune to the disease were considered unemployable. This disproportionally impacted migrants and people of colour, who were forced by their conditions to keep earning money, while wealthy white families and business owners could retreat indoors for protection.

The ACLU has warned immunity passports could form part of “a new health surveillance infrastructure that endangers privacy rights”, a concern shared by Ella Jakubowska at European Digital Rights (EDRi), an association of civil and human rights organisations from across Europe. Jakubowska says that “combining health data with biometric data further increases the ability of states to build up highly detailed, intrusive and intimate records of people”, including housing, employment and travel history. “This can, in turn, have a chilling effect on freedom of expression” with governments using immunity passports to restrict freedom of movement under the pretext of fighting the pandemic.

The tension of balancing civil liberties with collecting big data is nothing new. What matters is how governments strike that balance between freedom and security. China’s mass surveillance network, which has previously come under criticism from Western media as overreaching, has proven remarkably effective in managing Covid-19.

However, in an interview with the BBC, Adam Schwartz, a senior lawyer at the Electronic Frontier Foundation in California, said historically governments have been reluctant to wind back security powers after they’ve been introduced. “For example, in the wake of the 9/11 attacks, the US created vast new surveillance powers. Nineteen years later, those powers are still very much in the hands of the US government.” This retention of special powers beyond the scope of which they were originally intended is referred to as “mission creep” and experts warn Covid-19 may usher in a new age of global digital surveillance.

Governments are already in the unenviable position of balancing public health with the need to revive the economy. While immunity passports appear, on the surface, to be a panacea to reviving tourism and a significant chunk of the global economy, they also bring the added complexity of human rights to a table already groaning under the weight of a once-in-a-century event.

Future of Travel is a series from BBC Travel that investigates what the world might look like to travellers in the coming years and meets the people living on the frontlines of change.

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