The World Health Organization has warned governments against issuing “immunity passports” to allow people who show antibodies for coronavirus to return to work.
As leaders across the world turn their focus to reopening their economies after weeks of social restrictions designed to contain the pandemic, many have been hoping to deploy some form of certificate system allowing people deemed immune to travel and work.
But in a scientific brief published on Friday evening, the WHO cautioned against such plans, citing a lack of proof that anyone could be definitively labelled immune from the deadly virus.
“There is currently no evidence that people who have recovered from Covid-19 and have antibodies are protected from a second infection,” the WHO said.
Chile last week became the first country to announce plans to give “health passports” to recovered Covid-19 patients, allowing them to go back to work, Reuters reported.
Germany and the UK have also considered taking a similar approach to help ease the strains on economies suffering their sharpest contractions in decades.
However, the WHO said there was not yet enough evidence to guarantee that such measures would work, and that there were no studies on whether the presence of antibodies indicated immunity in humans. It said giving people who have antibodies special rights to travel or work “may therefore increase the risks of continued transmission”.
Reports of 51 patients in South Korea who tested positive after apparently recovering from the virus, as well as similar cases in Japan and China, have raised concerns over scientists’ understanding of Covid-19 immunity.
On Saturday, the WHO issued a further statement on the matter, via Twitter.
“Earlier today we tweeted about a new WHO scientific brief on ‘immunity passports’. The thread caused some concern & we would like to clarify: We expect that most people who are infected with #COVID19 will develop an antibody response that will provide some level of protection,” the WHO said.
The WHO also cautioned on the accuracy of antibody tests used to determine immunity and the risk of confusing Covid-19 antibodies with those for other coronaviruses, including four viruses that cause the common cold.