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My local drugstore now offers antibody testing. Do I have to pay a fee to find out how protected I am against COVID?
Although there are more antibody tests available, the truth is that they are not yet widely available. Experts answered this question. They explained why serology tests, also known as antibody tests, are not useful for most people and why you shouldn’t change any of your behavior based upon the results.
First, some background. A COVID-19 antibody testing measures one component in your body’s immune reaction to the coronavirus vaccine or COVID-19 virus. An antibody test does not determine whether you have COVID-19, unlike PCR tests or the often difficult-to-find rapid antibodies. Cynthia Leifer, a Cornell University professor in Microbiology and Immunology, says that an antibody test cannot determine if you are currently infected.
Antibody tests examine a sample from your blood to determine if your immune system has reacted to being infected by the SARS-CoV-2 virus or from receiving a COVID-19 vaccination. The test measures the amount of antibodies in your blood. A positive result means that you have likely been exposed to some degree. If your result is negative, it could indicate that you have not been exposed to the vaccine or coronavirus.
The idea of an immunity passport that was based on antibodies seemed promising in the early days of the coronavirus pandemic. But, “the question that everyone wants to answer is: Am I protected?” Leifer states that an antibody test is not a good option.
There are many reasons for this. Leifer states that there are many reasons why antibody protection from vaccines and other exposures differs greatly.
She also says that the required amount of antibodies for protection varies between people. A study of 1,497 Israeli health care workers that was fully vaccinated has shown a correlation between higher levels antibodies and greater protection. However, it is impossible to determine how high an antibody level should be.
Leifer also points out that not all antibodies are created equal. At the first sign of an exposure, your body will produce IgM antibodies. Then, it switches to IgGs which are more effective in protecting you against viral diseases such as COVID-19. Your level of protection could be affected if you have too many of one type of antibodies and not enough of the other. Most tests don’t show the difference, and even those that do tell you can only be marginally more helpful since there is no standard threshold for determining how protected you are.
The antibodies are not the only thing that will protect you against COVID-19. When activated by a virus or vaccine, T cells that attack infected cell cells will also help you. This response is not currently measured by any test. (Plus, the immune system has another arm that helps to clear the virus.
A positive test is a simple way to find out if you have had the vaccine. This shouldn’t surprise anyone! You will not know how protected you are if you have been exposed to the virus. Even if you don’t have the vaccine, you may still be tempted to get an antibody test to check if you are infected. However, this doesn’t guarantee that you won’t become infected again. No matter what the outcome, public health agencies recommend that you get vaccinated.
The FDA doesn’t recommend these tests as a way to test your immunity, even though the Food and Drug Administration has approved dozens of antibodies to be used to identify people who may have developed an adaptive immune reaction to SARS-CoV-2.
Is there a potential use for an anti-body test?
Baker and Leifer agree that these tests can prove to be extremely useful in studying the entire population. Baker says that antibody tests can be used to help researchers determine how many of the virus is present. She adds that researchers use antibodies to determine how long antibodies can last. This could be useful in helping scientists decide the best timing and amount of booster shots. Antibody tests are being used in research right now.
Baker suggests that you contact your doctor, an urgent care center provider, or your local health department if you believe an antibody test may be helpful for your personal health. Ask your doctor or pharmacist which test they offer. The FDA website will provide information about the accuracy of that test and whether you will receive specific levels, or a general “positive”/”negative” result.
If you want to find out if your COVID-19 was present, you can do a blood test. Baker believes that an antibody test may give you a more meaningful result when more information is available about your protection. You’re likely out of luck for now.
Sheila Mulrooney Eldred, a freelance journalist covering health in Minneapolis, is Sheila Mulrooney Eldred. Sheila Mulrooney Eldred has written extensively about COVID-19 in many publications, including The New York Times and Kaiser Health News. More at sheilaeldred.pressfolios.com. Follow @milepostmedia on Twitter