What coronavirus antibody tests tell us — and what they don’t
As some countries begin to reopen in the midst of the ongoing coronavirus pandemic, experts are racing to ramp up the development and use ofblood tests that pinpoint people who have been exposed to the virus that causes COVID-19 and are no longer infected. The tests detect antibodies, proteins made by the immune system to fight infection (SN: 3/27/20). People who carry antibodies specific to the novel coronavirus, called SARS-CoV-2, have been infected previously, even if they didn’t know it. For those people, discovering that they have these virus-fighting antibodies could raise hopes of immunity and a return to normal life. But scientists are also working to uncover what these blood tests really tell us. At this point, there isn’t enough evidence to confirm that recovered people are protected from the disease and, if so, for how long, the World Health Organization said in a statement on April 24. So people hoping for that assurance may be disappointed. For researchers and public health officials, though,...