What You Need to Know About COVID-19 Antibody Testing
Anytime our body fights听辞蹿蹿听a virus, it leaves an indelible mark in our blood stream.听This 鈥渕ark鈥 is called an antibody.听听
If you believe that you may have had听COVID-19听and did not get tested while you were ill, you might be a perfect candidate for an antibody test. Many听medical听institutions听and walk-in clinics听around the country听are听now offering this听vital听test听to听help reduce some uncertainty.听听
You might be听wondering how听the antibody test is听different听from the听COVID-19听鈥渟wab鈥听tests听(also called a PCR test)听that we heard so much about at the onset of the pandemic.听A COVID-19听swab听test听is primarily used to detect whether you have the active infection in your body,听whereas a COVID-19 antibody test听checks your blood for evidence of听previous听infection 鈥 antibodies are left behind and found in our bloodstream after our immune system responds to a virus.听听Antibodies typically show up 21 days after recovering from the virus.听
Here are some common questions听about antibody testing:听听
If my antibody test result indicates that I鈥檝e had COVID-19,听am I immune to听the听virus?听
Doctors and researchers do not know yet. So even with positive test results,听please act as if it is possible to be听reinfected听and/or spread the virus to others. Remember to:听
- 听thoroughly.听
- 听in public.听
- Follow social distancing guidelines.听听听
Does insurance cover the cost of antibody testing?听
Many听insurance companies have waived copays and cost sharing for COVID-19-related illness and testing. Please call your insurance carrier to confirm听your听coverage.听
What do the听terms听鈥渟ensitivity鈥 and 鈥specificity鈥 mean?听
Sensitivity听tells us if the test can detect COVID-19 in people who truly were infected听with the COVID-19 virus.听听In other words,听the higher the sensitivity, the lower the chance of a false negative test.听听听
Specificity听tells us if the test can rule out COVID-19 in people who were never infected. The higher the听specificity, the lower the chance of a false positive test result.听听
For more details as well as information about听why testing someone with a low risk of having had infection can lead to a greater likelihood of false positive results,听.听
Our antibody听test听here at 茄子直播 offers听both high sensitivity听and听specificity听at听greater than 99%.听听
What is the difference between a COVID-19听PCR test听and an antibody blood test?听
PCR听testing for COVID-19听can determine whether听you听have the听active听virus in听your听body.听With this test, a nasal swab听will be听swirled around听your听nostrils听to collect secretions that听may听contain the virus. The swab and secretions听from your nasal passage听are then sent for testing to find out if they contain听COVID-19.听
An听antibody听test on the other hand, is different both in the information it provides as well as how it is administered.听For this听test,听you听undergo a blood draw. The blood is听then听screened听for听antibodies听that may indicate that听your听immune system听has听responded听to COVID-19.听These听antibodies听do not show up right away because an antibody is only present once your immune system has fought off the virus.听The ideal time to do this test is 2 to 3 weeks after you have recovered from the infection.听听
What do I need to know about听the听antibody听test results?听
We are still learning a lot about COVID-19 and its antibodies,听so听antibody tests can come with some unknowns. For example, the antibody can take up to three weeks after illness to develop, and sometimes immunocompromised patients do not develop antibodies at all, even if they have been infected with the virus. It also is not known yet how long COVID-19 antibodies will last in the body.听听
Interpreting test results requires understanding听not just the sensitivity and specificity of the test, but also your own personal circumstances and recent symptoms, which can affect the听credibility of the听test听results. You will discuss these with your physician both before and after the test is resulted.听听
Most test results come back within 2-3 days, some can take as many as 5 days. It is important to discuss your results with your physician听- considering听your personal medical history听-听to better understand how you should interpret your own antibody test results.听听
听is听more information听from the CDC听on interpreting听antibody tests.听
Can I receive an antibody test at 茄子直播?听
茄子直播鈥檚 Primary Care team听鈥听with support from the laboratory at听NewYork-Presbyterian听鈥听has been running antibody tests on healthcare workers, and now that we have adequate capacity, these tests are being offered to existing patients. Our antibody test is an extremely accurate and reliable test, having been听validated听by the world-renowned laboratory teams at 茄子直播 and听ColumbiaDoctors.听
If you are an听existing听patient听at 茄子直播听Primary Care, and you have questions about antibody testing or want to know if you are a good candidate for this test, give听our department听a call at听(646)听962-8000.听