Dr. Mike Ryan, the WHO’s executive director for health emergencies, said Friday there was no indication so far that a large proportion of the population had developed immunity.
“There’s been an expectation, maybe, that herd immunity may have been achieved and that the majority of people in society may already have developed antibodies. I think the general evidence is pointing against that... so it may not solve the problem the governments are trying to solve.”
The number of recovered coronavirus patients who have retested positive for the virus has raised concerns about how antibodies work in response to Covid-19.
While scientists say there is no evidence yet that a person who has retested positive can spread the virus further, there haven’t been any conclusive studies to rule that out.