From CDC on antibody tests: A positive test result shows you may have antibodies from an infection with the virus that causes COVID-19. However, there is a cha

From CDC on antibody tests: A positive test result shows you may have antibodies from an infection with the virus that causes COVID-19. However, there is a chance a positive result means that you have antibodies from an infection with a virus from the same family of viruses (called coronaviruses), such as the one that causes the common cold. https://www.cdc.gov/coronavirus/2019-ncov/testing/serology-overview.html https://www.cdc.gov/coronavirus/2019-ncov/testing/serology-o... I have not read enough on this specific NYC testing to know for sure if they control for that somehow, or if controlling for it is even possible. Seems like it would be a factor, though.