The World Health Organisation (WHO) is urging governments not to issue "immunity passports" to people who have recovered from the novel Coronavirus (Covid-19).
The international health body recalled that there was no proof that people who have been infected and survived cannot be re-infected, an idea that has been circulating in recent weeks as countries mount deconfinement strategies.
Some officials have suggested a type of "immunity" certificate for people who can prove that they have developed antibodies to SARS-CoV-2, so as to enable them to resume their normal lives without delay.
However, WHO said in a briefing note on Saturday, "at this point in the pandemic, there is not enough evidence about the effectiveness of antibody-mediated immunity to guarantee the accuracy of an 'immunity passport' or 'risk-free certificate'."
There is no evidence that people who have recovered from Covid-19 and have antibodies are protected against re-infection, WHO stressed, warning that "immunity passports" could increase transmission of the virus since people who assumed they were immune might stop taking precautions.
Various antibody tests are on the market, but they are not always reliable. Still, WHO encourages the tests since they are essential to understanding the extent of the infection and the attendant risk factors.
The Brussels Times