And yet, despite the ultra high numbers of positive tests recorded daily, and the fact that I’d feel comfortable guessing anyone reading this knows at least one person who’s been tested, many are still confused about testing. Many are still unclear when it comes to understanding what are the different kinds of tests out there. How do we interpret the results? How do the results affect what we do next?
Scary Mommy spoke with Dr. Sunitha D. Posina MD, a board-certified internist who served on the frontlines of the pandemic by taking care of critically ill COVID-19 patients in New York, the nation’s first epicenter.
Know The Difference: Diagnostic Test Versus Antibody Test
A diagnostic test is looking for the virus and can tell you whether you have an active infection. These tests are completed via nasal swab, throat swab, or spit test. An antibody test tests your blood to determine whether your body has developed antibodies to a previous infection.
Types Of Diagnostic Tests
There are two types of diagnostic tests on the market right now: the PCR test and the antigen test (not to be confused with the antibody test). Both tests look for an active infection, but have very different mechanisms.
According to Dr. Posina, a PCR test, also called a molecular test, tries to detect the viral genetic material in your body, whereas an antigen test searches for a protein, the antigen of the virus. The majority of tests that were initially rolled out in March were PCR tests, which tend to take longer to process—although more rapid tests have been developed recently. These types of tests tend to be more accurate. Antigen tests, on the other hand, are capable of returning results faster, though they are more likely to return a false negative.
Many antigen tests can return same day results. Some PCR tests are also beginning to deliver rapid results.
Which Test Should I Get?
Before deciding which test you should get, ask yourself why you’re being tested. If you are currently exhibiting symptoms or you have been exposed to someone who later tested positive for COVID-19, then you should ask your doctor for a diagnostic test.
At the testing center, the medical professional offering the test will most likely determine whether a PCR test or an antigen test is more appropriate for you. If you’re showing common COVID-19 symptoms, such as fever, cough, or shortness of breath (among many others included on the CDC’s list of symptoms), most likely you will be tested with an antigen test, as the results are faster. If you are requesting a COVID-19 test because you’ve been exposed to someone who was infected with the virus, but are not currently exhibiting symptoms, you will most likely be tested using the PCR test.
If you previously tested positive and two to three weeks, at least, have passed since your last symptom, you can get tested for antibodies. An antibody test looks in your blood for the proteins that your body produces to fight the infection.
When Should I Get A Diagnostic Test?
Dr. Posina suggests that the best time to get tested is within a day or two of symptoms appearing, or four to five days after a potential exposure, even if no symptoms have developed. According to Dr. Posina, “97.5% of people become symptomatic between the 4th and 11th day of exposure, and what that suggests is that most people have that virus from day four or five.”
What Are The Brand Names Of The Most Reliable Tests?
Most of the diagnostic tests from Labcorp, Quest, Abbott, FIA, Roche are reliable and readily available. None are 100% accurate, according to Posina, but most of the time, the accuracy of these brands is pretty reasonable. If there’s high suspicion of incorrect testing, she would suggest retesting.
Will My Insurance Cover Testing?
Congress passed the Families First Coronavirus Response Act requiring insurers to pay for testing deemed “medically necessary”. However, Dr. Posina warns that things may soon be changing and the question of what is “medically necessary” is being debated by health plans. She suggests checking with your independent insurer.
What Does It Mean To Test Positive For Antibodies?
The truth is that we don’t yet know what it means if someone tests positive for antibodies. Typically antibodies are associated with immunity, and testing positive for antibodies might provide some comfort in the knowledge that you had and fought off the virus, says Dr. Posina. However, the antibodies may not be COVID-19 antibodies; they could belong to a previous coronavirus infection that you fought off. (We tend to think of “coronavirus” as being COVID-19, but there are actually seven types of coronavirus known to infect humans.)
“We’re still evolving in our learning process. If you have antibodies, it’s a reassurance, but there’s no scientific data whether the antibodies offer immunity and if they do, how much immunity they offer and the duration of that immunity,” says Dr. Posina.
Is Social Distancing Needed If I Have Antibodies?
The answer: Absolutely. Dr. Posina stresses that a positive antibody test is important because it’s a small amount of reassurance and it provides public health officials with important data regarding the disease. But, there’s no guarantee that the antibodies detected by the test were created in response to COVID-19, and no proven information on what kind of immunity, if any, the antibodies offer. It’s important, therefore, to wear a mask, social distance, and practice all the measures.
Can Children Get The Antibody Test?
Yes, but as with adults, the results are nonspecific and should not change how you navigate this pandemic.
Testing, both diagnostic and antibody, is key to understanding and stopping the spread of this virus. The more we can understand the patterns of spread, of infection, the more tools and weapons scientists and medical professionals will have to get this virus under control. And in the meantime, continue social distancing, continue wearing your mask, continue following the rules set by public health officials.