With more than half of our world in lockdown, many people are seeking an end to restrictions and wondering how we can ease the situation before vaccines are widely available.
Certain governments have suggested that the detection of antibodies to the SARS-CoV-2, the virus that causes COVID-19, could serve as the basis for a “risk-free certificate” that would enable individuals to travel or to return to work assuming that they are protected against re-infection.
For instance, researchers in Germany are exploring the idea of “immunity passports” to try and determine who has already built up an immunity to the Coronavirus and who could therefore be able to go back to a work or travel routine. The UK government has also expressed an interest in going down a similar route. Might such documentation have to be presented when booking international travel once the social restrictions start to ease?
They are proposing that certificates would be available for all who have had the virus, recovered successfully and can prove they are immune now. But how can you prove immunity? Who would be able to issue such a passport or certificate and when/where would it be available?
Authorities would have to find a standardized antibody testing method in a healthcare facility rather than at home – once a reliable way of testing has been approved – to avoid fraudulent reporting in order to gain more freedom. However, the WHO believes that laboratory tests that detect antibodies to SARS-CoV-2 in humans, including rapid immunodiagnostic tests, require further validation to determine their accuracy and reliability. Inaccurate immunodiagnostic tests may falsely categorize people in two ways: either by falsely labelling people who have been infected as negative, or by labeling those who have not been infected as positive.
Should be able to prove immunity, there must be a way to issue these certificates and to ensure they cannot be duplicated. The question will remain as to how to create a document that will be widely accepted, even outside the country of issue, without violating personal rights and exposing private data, which might be the biggest challenge.
In conjunction with e-commerce company Alibaba, the local Chinese government is working to implement a system currently only available in certain regions of the country. Called Alipay Health Code, this will require people to register through Alibaba’s wallet app, Alipay. Each applicant will be assigned a color code - green, yellow or red — to indicate their health status. Further information will be required from Alibaba and government officials as to how the system of classification is assessed.
Once users complete the form on Alipay, the software generates a QR code in one of the three colors reflective of personal details. A green code enables unrestricted movement, yellow codes may require a home stay for 7 days, and red codes require a two-week quarantine. This way the QR code controls access to public transportation.
Why haven’t other countries started to do this already?
With the methods China is implementing, many western countries would be facing data protection regulations that make it hard to collect all the information. Further, the lack of absolute certainty that the immunity of people who have had Covid-19 is strong enough to avoid further infection is possibly another factor.
The WHO shares these concerns and is not in favor of the passports\certificates as they believe that there is currently no scientific evidence that people who have recovered from Covid-19 and have antibodies are protected from a second infection. However, most of the studies show that people who have recovered from infection have antibodies to the virus, but some of these people have very low levels of neutralizing antibodies in their blood, suggesting that cellular immunity may also be critical for recovery. As of 24 April 2020, no study has evaluated whether the presence of antibodies to SARS-CoV-2 confers immunity to subsequent infection by this virus in humans.
Theoretically the idea of immunity passports could possibly help ease the situation to enable people to start travelling again. However, it is critical to develop a more robust system, with scientific validation of anti-body tests, that is standardized around the world. The WHO is working on a global approach that will hopefully be available by the summer and help getting back to normal.