<span style="color: #222222;">The World Health Organization is cautioning against the idea of immunity passports. It says there is currently no evidence that people who have recovered from COVID-19 and have antibodies are protected against a second infection.<br />''<br />''The concept of immunity passports or risk-free certificates has been floated as a way of allowing people protected against reinfection to return to work.<br />''<br />''WHO  argues that people who assume they are immune to reinfection may ignore public health advice, and such certificates could raise the risks of continued virus transmission.</span><br />