Scientists still don’t know whether coronavirus antibodies give a person immunity or reduce the risk of reinfection, even as some nations consider issuing passports or certificates that indicate whether someone has had the virus, World Health Organization officials said.
Some countries are considering issuing so-called immunity passports or risk-free certificates to people who have antibodies against Covid-19, enabling them to travel or return to work assuming that they are protected against reinfection, Dr. Maria Van Kerkhove, head of WHO’s emerging diseases and zoonosis unit, told reporters during a news conference at the agency’s headquarters in Geneva.
But right now, scientists are unsure whether an antibody response means someone is immune from the virus, she said, adding researchers do know a person typically develops an antibody response about one to two weeks after becoming infected with Covid-19.
WHO officials are studying the so-called serological, or antibody, tests, which can indicate whether a person has had Covid-19 in the past and was either asymptomatic or recovered from the illness. U.S. officials and corporations across America are pouring money into antibody testing, hoping it will give people confidence to return to work and reopen parts of the economy.