Covid-19 Antibody Tests in Demand as People Worry About Immunity

Some people are taking Covid-19 antibody tests to determine whether they might be protected against the virus. Many health officials and doctors wish they wouldn’t.

Antibody tests are one tool some people are deploying to help them decide which precautions to take to protect themselves and curb the spread of Covid-19. Some vaccinated people say they want to know whether their protection has weakened to the point that they should get a booster, while some previously infected people say they want to measure the strength of the response the virus generated in their...