Serology testing for COVID-19 at CDC

Updated Nov. 3, 2020CDC has developed a laboratory test to help estimate how many people in the United States have been infected with SARS-CoV-2, the virus that causes COVID-19. Clinicians and researchers refer to this as a serology test, and many commercial laboratories call it an antibody test. CDC is using this serologic (antibody) test to evaluate the performance of commercial antibody tests. CDC will develop guidance for the use of antibody tests in clinical and public health settings.An antibody test looks for the presence of antibodies, which are specific proteins made in response to infections. Antibodies are detected in the blood of people who are tested after infection; they show an immune response to the infection. Antibody test results are especially important for detecting previous infections in people who had few or no symptoms.We do not know if the antibodies that result from SARS-CoV-2 infection will provide someone with protection (immunity) from getting infected again. If antibodies do provide immunity, we don\u2019t know how much antibody is protective or how long protection might last. CDC scientists are currently conducting studies to answer these questions.CDC\u2019s serologic test has been designed and validated for surveillance and research purposes. It is designed to estimate the percentage of the U.S. population previously infected with the virus \u2013 information needed to guide the response to the pandemic and protect the public\u2019s health.The CDC test is not currently designed to test individuals who want to know if they have been previously infected with SARS-CoV-2. Commercial tests are available to provide test results to individuals.CDC is evaluating the performance of commercial antibody tests -- Limitations of antibody tests -- Guidance for clinicians on optimizing testing outcomes -- About CDC\u2019s serologic test -- CDC serology surveillance strategy.2020874