World Health Organization (WHO) has said that there is currently no evidence that people who have recovered from COVID-19 and have antibodies are protected from a second infection. WHO said no study has evaluated whether the presence of antibodies to SARS-CoV-2 confers immunity to subsequent infection by this virus in humans.

WHO said there is still a lack of sufficient evidence for the effectiveness of antibody-mediated immunity to guarantee the accuracy of an immunity passport or risk-free certificate. According to the UN agency, laboratory tests that detect antibodies to SARS-CoV-2 in people, including rapid immunodiagnostic tests, need further validation to determine their accuracy and reliability.