South Texas Health System is now offering antibody testing at two freestanding emergency department (FED) locations: STHS ER Alamo and STHS ER Ware Road. Pricing for the test is $50 self pay. No physician order is required for the test. Patients can walk in and have the test done upon request.

Testing is available Monday – Friday, 8 am – 5 pm.

To learn more, call STHS ER Alamo at 956-403-5100, or STHS ER Ware Road at 956-213-2700.

What is the COVID-19 antibody test?

Test results may help identify if you were previously exposed to the COVID-19 virus and whether your immune system has produced antibodies.

Note: This test does not detect if you currently have COVID-19. The test can sometimes detect antibodies from other coronaviruses, which can cause a false positive result if you have been previously diagnosed with or exposed to other types of coronaviruses. Further, if you test too soon, your body may not have produced enough IgM/IgG antibodies to be detected by the test yet, which can lead to a false negative result.

Who is the COVID-19 antibody test appropriate for?

This test may be helpful if you:

  • Have had a positive test for COVID-19 and it has been at least 10 days since you were tested, and you want to know if you have detectable levels of IgM/IgG antibodies
  • Have experienced symptoms of COVID-19 in the past few weeks: fever, fatigue, vomiting or diarrhea, loss of smell or taste, shortness of breath or difficulty breathing

This test may NOT be helpful if you:

  • Feel sick or have had a fever within the last three full days; please contact a healthcare provider
  • Are trying to diagnose COVID-19; please contact a healthcare provider
  • Have had a positive test for COVID-19 and it has been less than 10 days since you were tested
  • Have been directly exposed to COVID-19 in the past 14 days

You may still have an active COVID-19 infection and this test may not be right for you at this time.

Is fasting required for the COVID-19 antibody test?

No, fasting is not required.

What do I need to know before I arrive at a testing center?

We require that all patients be screened and wear a mask or face covering in our center.

How do I interpret my lab results?

South Texas Health System strongly recommends you share your results with your physician to make decisions for your health.

Positive: You produced the COVID-19 IgM/IgG antibody and have a high likelihood of prior infection.

  • Some patients with past infections may not have experienced any symptoms. It is unclear at this time if a positive IgM/IgG infers immunity against future COVID-19 infection. Please continue with CDC recommendations: social distancing, hand washing and masks or gloves as appropriate.

Negative: You tested negative for COVID-19 IgM/IgG antibody. This may mean you have not been infected with COVID-19.

  • Please note, it may take 14-21 days to produce detectable levels of IgM/IgG following infection. If you had symptoms consistent with COVID-19 within the past three weeks and tested negative, a repeat test in 1-2 weeks may yield a positive result.

Equivocal: Your test results could not be interpreted as Positive or Negative.

  • The most common reasons for equivocal results are presence of an immune response but it's unclear if you are immune to the infection being tested for (COVID-19 in this case) or similar infections (the common cold is a type of coronavirus). If indicated, a repeat test may yield more reliable results.

Can I use the COVID-19 antibody test to determine when to stop isolation or go back to work?

The CDC recommends you discuss your results, and whether to return to work, with your healthcare provider and employer.

How do I get my lab test results?

You can access your results through our secure online patient portal, Health Records Online.

How long does it take to get my lab test results?

Your lab tests results will be available within 48 hours.

Is the COVID-19 antibody test FDA approved/cleared?

This test has been authorized by the FDA under an Emergency Use Authorization (EUA) for use by authorized laboratories. This test has not been FDA cleared or approved. The FDA has reviewed and authorized the testing under specific circumstances, because it is reasonable to believe that the testing may be effective, but additional studies need to be conducted for the testing to be FDA cleared or approved.