World Health Organization officials said not all people who recover from the coronavirus have the antibodies to fight a second infection. This raises concerns that patients don’t develop immunity after surviving Covid-19.
“With regards to recovery and then re-infection, I believe we do not have the answers to that. That is an unknown,” Dr. Mike Ryan, executive director of WHO’s emergencies program, said at a press conference at the organization’s Geneva headquarters on Monday.
A preliminary study of patients in Shanghai found that some patients had “no detectable antibody response” while others had a very high response, said Dr. Maria Van Kerkhove, WHO’s lead scientist on Covid-19. Whether the patients who had a strong antibody response were immune to a second infection is “a separate question,” she added.
More than 300,000 of the 1.87 million coronavirus cases across the world have recovered, WHO officials noted, adding that they need more data from recovered patients to understand their antibody response, whether that gives them immunity and for how long.
“That’s something that we really need to better understand is what does that antibody response look like in terms of immunity,” Van Kerkhove said.
