COVID-19 antibody testing: When is it most useful?

As more individuals who have been vaccinated against COVID-19 reach the point that they need a booster shot, and some unvaccinated people look for a reason not to get a shot, demand for COVID-19 antibody tests has grown. Many see those test results as a way to determine if they have the immunity they need to keep them safe from the virus.

But COVID-19 antibody tests are not recommended as a reliable tool for measuring immunity. An article recently published in the Wall Street Journal explored when antibody testing is valuable, and why it should not be used by individuals as a gauge of protection against COVID-19.

Elitza Theel, Ph.D., who directs Mayo Clinic’s Infectious Diseases Serology Laboratory, contributed to the discussion. She noted that although the tests can detect antibodies to COVID-19, they don’t provide comprehensive information about overall immunity. “Antibody testing doesn’t give you a full picture of a person’s immune response to COVID. It just shows you a snapshot of one branch of the immune system,” Dr. Theel says.

The article explained that public health experts, immunologists, and other specialists do find COVID-19 antibody tests useful for studying immune response in certain individuals, such as immunocompromised patients, and for measuring trends in infection across large groups of people. But scientists have not identified a level of antibodies that corresponds with protection against COVID-19. That means antibody tests have limited value for most people looking to assess their immunity to the virus.

Read the full story here.