Serology Testing: Understanding Antibody Testing for COVID-19

A serology 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. Serology test results are especially important for detecting previous infections in people who had few or no symptoms. The following information focuses on serology testing in relationship to COVID-19.

What does serology testing for SARS-CoV2 (COVID-19) mean? If your antibody testing for COVID-19 is positive, it most likely means that you have previously been infected with COVID-19. If you had prior symptoms that were typical of COVID-19 (fever, cough, shortness of breath, sore throat, loss of taste or smell) since mid-March, it is likely those symptoms were caused by COVID-19. It is possible to have been infected with COVID-19 without having any symptoms, but it is also possible, though rare on a highly accurate test, for a person to have a false positive antibody test.

Are all antibody tests the same? No. The body makes many different antibodies to any virus. Antibody tests can test for any of these many different antibodies. Also, some tests are more accurate than others. Many antibody tests that have been sold for COVID-19 have not been proven to be accurate because they were hastily developed. The antibody test used at Iowa Specialty Hospitals & Clinics was developed by Abbott Laboratories, which is a well-established lab that did proper research to show that the test is accurate more than 99% of the time.

Will an antibody test be positive immediately after infection? No, it takes time to develop antibodies. We recommend waiting at least 14 days after a suspected infection to have an antibody test. If you are concerned that your current symptoms are because of COVID-19, a different type of test that requires a swab of the nose is a better option.

If I have a positive antibody test for COVID-19, am I immune? For most infections having a positive antibody test means that a person is at least temporarily immune. Unfortunately, COVID-19 is such a new illness that scientists have not been able to determine for sure whether this is true for COVID-19. It may be that having antibodies provides immunity for months or even years, but it is also possible that if the virus mutates the person would not be immune to the new mutated strain.

Do I have to follow social distancing precautions and wear a mask if I have a positive antibody test? We strongly recommend continuing to wear a mask or face shield and continuing social distancing precautions even if you have a positive antibody test. This is important because even if you have immunity, you may still be able to spread the virus to others. For that reason, it is wise to continue to follow the same precautions everyone else does even if you have a positive antibody test.

If I still have to follow the same precautions, what is the benefit of having the test? Knowing that someone has antibodies for COVID-19 is useful for three main reasons. First, current public health guidelines do not recommend quarantine for someone exposed to COVID-19 if there is documentation that they have already been infected. Serology can help document whether someone has been previously infected. Second, someone with antibodies can donate plasma that contains these antibodies to use as a treatment for other individuals who become sick with COVID-19. Third, knowing how many people have had COVID-19 in the past helps medical personnel and government leaders better understand how much risk of further spread there is in different parts of the country. When more people have been previously infected, it becomes harder for the virus to spread in an area.

How do I get tested and how much will it cost me? If you have not previously tested positive for COVID or been symptomatic but would like to have the antibody testing, you can present to Iowa Specialty Hospitals & Clinics’ Clarion or Belmond main campuses, Monday-Friday from 8:00 am – 4:00 pm, and request the Wellness COVID-19 antibody testing. The cost for this test is $30.00 and payment will be due at the time of testing.

If you have previously tested positive for COVID, then the serology testing could be billed to your insurance. Per the Federal mandate it would be covered at 100% by insurance as preventative care during this public health emergency if ordered by a provider based on direct exposure or relevant symptoms (fever, cough, shortness of breath, sore throat, loss of taste or smell). Please call your provider office to request an order if you would like it billed to insurance.

What do I do if I have questions about my test results? Please call Iowa Specialty Hospitals & Clinics at 844-474- 4321 to set up a consultation visit with your healthcare provider. For your safety and convenience this appointment can be provided via telehealth, telephone, or face-to-face.