Only a tiny proportion of the global population – maybe as few as 2% or 3% – appear to have antibodies in the blood showing they have been infected with Covid-19, according to the
World Health Organization, a finding that bodes ill for hopes that herd immunity will ease the exit from lockdown.
“Easing restrictions is not the end of the epidemic in any country,” said WHO director-general Dr Tedros Adhanom Ghebreyesus at a media briefing in Geneva on Monday. “So-called lockdowns can help to take the heat out of a country’s epidemic.”
But serological testing to find out how large a proportion of the population have had the infection and developed antibodies to it – which it is hoped will mean they have some level of immunity – suggests that the numbers are low.
“Early data suggests that a relatively small percentage of the populations may have been infected,” Tedros said. “Not more than 2%-3%.”
Dr Maria Van Kerkhove, an American infectious diseases expert who is the WHO’s technical lead on Covid-19, said they had thought the number of people infected would be higher, but she stressed it was still too early to be sure. “Initially, we see a lower proportion of people with antibodies than we were expecting,” she said. “A lower number of people are infected.”