When will life return to normal, or at least a new normal?
A major answer to the question of when — and how — Americans can return to public places … could depend on something called an antibody test, a blood test that determines whether someone has ever been infected with the coronavirus.
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What exactly is a serology test?
A serology test looks for signs of an immune response — in this case, to the new coronavirus.
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What can these tests tell us? And what can’t they?
Let’s begin with what they can’t tell us. Because the antibodies come up so late, these tests are not helpful for diagnosing an early infection. …
The tests are more effective at detecting the presence of antibody responses across large numbers of people, not just to determine who is immune but how widely the virus has spread in the population.
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I’m pretty sure I had the coronavirus already. Can I take a test and go back to work?
Not yet. Most of the tests being developed offer a simple yes-no answer to the question of who has antibodies, and who was exposed to the virus. But simply having antibodies is no guarantee of immunity.
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If someone is immune to the virus, how long will the immunity last?
We don’t know.
