In an announcement that underscored the scientific unknowns about the virus, the World Health Organization said “there is currently no evidence” that people who have recovered from COVID-19 cannot fall sick again.
The warning comes after some governments around the world suggested issuing so-called "immunity passports." They would allow people who already tested positive for COVID-19 to return to work or travel.
WHO says there is simply not enough research to support immunity claims because of the presence of antibodies.
Also on Saturday, the global death toll from the novel virus surpassed 200,000, according to researchers at Johns Hopkins University.
Associated Press wire services contributed to this report.
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