The world of COVID-19 is ever-changing. While scientists and medical experts are tirelessly searching for an answer to combat the virus, there’s still much we have to learn about it. In addition to diagnostic coronavirus testing, Crystal Run Healthcare is conducting antibody testing. With all of the questions surrounding antibody testing, Dr. Gregory Spencer, chief medical officer and chief medical information officer at Crystal Run Healthcare, provides us with answers on what we know now.
What is antibody testing?
When you are infected with SARS-CoV-2, the virus that causes COVID-19, your body fights the infection and makes antibodies. You can also get antibodies from a vaccine for a disease — but one hasn’t been developed yet for COVID-19. Antibodies show if you’ve had a previous infection with the virus. Antibody tests look into the past and determine whether you were infected with the virus more than two to three weeks prior. This is different than a virus test, which you may hear called one of many different names: “molecular,” “antigen,” “nucleic acid,” “RNA,” “PCR” or “nasal swab.” A virus test tells whether you are infected with the virus now.
Who should get tested?
Since a COVID-19 infection might not give you symptoms, anyone in an area where COVID-19 is present could consider getting an antibody test. Antibody tests show if you’ve previously had COVID-19, though that’s all the test can tell you right now. It doesn’t necessarily mean you’re immune. For an individual, it’s interesting to know. For big populations of people, however, it’s very useful. The test shows how many people in the population may have already been infected, which can help government and public health departments plan future responses. The test can also help identify people for convalescent plasma donors, as well as verification of vaccination response, if and when that becomes available.
What does a positive antibody test mean?
A positive test means you’ve had COVID-19 in the past. It does not mean you’re immune — whether this is the case remains to be seen. It’s not known if having antibodies will protect you against getting COVID-19 again. Even if you have antibodies, you still need to do what everyone else is doing to be safe, including social distancing and wearing a mask in public. It’s important not to get a false sense of security.
What does a negative antibody test mean?
A negative test means you either were not previously infected with the virus or you are very early in the course of infection and have not made detectable antibodies yet. A false negative test is also a possibility.
Are the antibody tests being offered any good?
The tests are very new and many have not undergone the full approval process by the Food and Drug Administration. That doesn’t mean a non-FDA approved test is bad, it just hasn’t been reviewed yet. There are concerns about tests cross-reacting and giving false positive results if you’ve been infected with another coronavirus recently. Coronaviruses are very common — about one in every three colds or upper respiratory illnesses are due to a different type of coronavirus that is not the same as SARS-CoV-2, but might be close enough to cause some tests to falsely turn positive.
Why would my antibody test be negative if I had COVID-19?
If you have had symptoms of COVID-19 and a positive nasal swab test, you very likely had the disease. There’s a chance your antibody test will be negative, however. How can this be? It takes a while for your body to make enough antibodies to be detectable by a test. Most of the currently available tests perform best at least 14 to 21 days after infection. If you check too early and are still in the process of making antibodies, the test might be negative. Other possibilities are that your body didn’t make a lot of antibodies in response to the infection and the level is too low for the test to pick them up, the test is in error, or there’s a small chance that you had a false positive nasal swab and didn’t actually have COVID-19. As stated above, early in the course of the disease, the antibody test may not yet give a positive result. That’s why it’s best to wait for three weeks or so after the illness before getting antibodies checked.
Your safety is our priority at Crystal Run Healthcare
It’s important to stay up-to-date on new developments with COVID-19. Following the Centers for Disease Control and Prevention guidelines and the guidelines of your local health officials is necessary and lifesaving.
More than 40 specialties at Crystal Run Healthcare are available through telehealth, many with same-day appointments. Visit the Crystal Run website to learn more and schedule an appointment using the telehealth request form. If you do need an in-person visit, we have made it as easy as possible and have implemented procedures to keep you safe in accordance with the CDC guidelines.
To learn more about Crystal Run Healthcare, visit crystalrunhealthcare.com and follow the practice on Twitter, LinkedIn and Facebook.