There is currently no evidence that people who have recovered from COVID-19 are subsequently immune to the disease, the World Health Organisation (WHO) stressed on Saturday, cautioning against the use of so-called "immunity passports".
Several nations and businesses have floated the idea of using "immunity passports" or "risk-free certificates" to allow people who contracted and recovered from the virus to travel or return to work, under the assumption that they are now protected from a second