Antibody testing has become an important topic in the country’s COVID-19 response. An antibody test checks a person’s blood by looking for antibodies, which show if you had a previous infection with COVID-19.
As a result of the pandemic, the U.S. Food and Drug Administration (FDA) has changed its regulations to make it easier for companies to sell novel coronavirus antibody tests. Any company can seek FDA approval to sell antibody tests, and those companies do not have to supply validation data that indicate their tests provide accurate results.
DHEC doesn't regulate laboratory testing, as that's done at the federal level by the FDA. However, we have communicated with the state’s private laboratories that the results of COVID-19 antibody testing should be reported to DHEC, and healthcare providers were given guidance on utilizing and reporting results from these tests.
Based on information from the CDC, DHEC advises that these tests are still investigational and aren't recommended to be used to diagnosis new cases of COVID-19. Antibody tests may have promise to inform treatments, disease surveillance, and determination of immunity after infection.
Please see additional information about COVID-19 antibody testing below.
Q. Will DHEC’s Public Health Laboratory offer antibody tests for COVID-19?
- Our Public Health Laboratory does not plan to offer this testing at this time.
Q. Does the presence of antibodies to COVID-19 mean the patient is infected?
- Not necessarily. It may indicate a past infection that has been cleared or a current infection which began within the past week or two.
Q. Does the presence of antibodies to COVID-19 mean the patient is no longer contagious?
- No, patients can still be shedding infectious virus even though they have an antibody response. It also doesn’t mean that they are immune because we don’t know if their antibodies are enough to keep someone immune or for how long.
Q. Does the presence of antibodies to COVID-19 mean the patient is immune to reinfection?
- We don’t know that yet. The antibody tests do not indicate whether the antibodies are neutralizing and protective or not.
Q. Are there any disadvantages or concerns with using the antibody tests, even the approved tests?
- Patients who are told their antibody test is negative may decrease social distancing efforts, thinking they are not infectious. This could be dangerous, as a patient can be infected and shedding virus to other people but not have developed antibodies yet.
Q. Can we use antibody test to determine if an employee can go back to work?
- Because the antibody test does not give information on the infectious status, it is not useful for this purpose. We refer to the latest CDC guidance for when infected employees may return to work.