Stay Informed about COVID-19 Antibody Testing
An antibody test checks for an immune response. If you have a positive antibody test for Covid-19, it means you may have been exposed and your body has created a memory. At this time, we do not know how long your immune system holds onto this memory nor do we know if you get re-exposed to the virus again if you will get sick again or not.
An antibody test does not determine rules regarding social distancing or clearance for returning to work. Having an antibody test done does not prevent you from getting Covid-19 in the future. The antibody test does not tell you if you have the virus now or if you are contagious.
Antibody testing cost may vary. It is not known if costs will be covered by insurance or if patient will be given a bill. It is important to understand the information about antibody testing before you have the test. Please call your doctor to discuss before you get tested.
The Following are some frequently asked questions around Coronavirus (COVID-19)
Q: What is SARS-CoV-2?
A: SARS-CoV-2 is the name for the virus that causes COVID-19. It is part of a large
family of coronaviruses, all of which typically cause respiratory disease in humans.
Q: What are antibodies?
A: Antibodies are proteins that develop when the immune system responds to a
pathogen, such as a virus. There are different types of antibodies, including ones called
IgM and IgG. IgM is the first antibody that develops after someone has an acute viral
infection. This is followed by the development of IgG antibodies. Once IgG antibodies
have been developed, if a person comes into contact with the same virus again, the IgG
antibodies help the immune system respond faster and more effectively than it did the
first time and may prevent illness.
Q: If an antibody (serology) test for SARS-CoV-2 antibodies is negative, does this mean I do not have
A: No. A serology test looks for the presence of proteins, called antibodies, which can be
used to help understand if you were exposed to the virus recently or in the past. A
person with a negative serology test could have the SARS-CoV-2 virus, but it is too early
to detect the antibodies on the serology test. Only a molecular diagnostic test can be
used to determine the presence or absence of the virus. Results from a serology test
should not be used as the sole basis for diagnosing if someone had COVID-19.
Q: If a serology test for SARS-CoV-2 antibodies is negative, but I had a molecular test
that said I was infected with the virus, what does this mean?
A: A person with a negative serology test could have the SARS-CoV-2 virus, but the
serology test is negative because it is too early to detect the antibodies since these take
time for the body to develop. A person can also have a negative serology test because
their immune system did not make enough of the antibodies to be detected by the test
after they were infected. Your healthcare provider will talk with you about what the next
steps should be, which may include repeating the serology test in the future.
Q: If the serology test is positive, does that mean that I have antibodies to the SARSCoV- 2 virus?
A: If the test used is only able to detect antibodies to SARS-CoV-2, then yes, a positive
test would indicate that you have antibodies to the SARS-CoV-2 virus. However, some
tests that detect antibodies to SARS-CoV-2 can yield false positive results due to
infection from other related coronaviruses; for these tests, a positive result may indicate
a previous exposure to a related virus and/or exposure to SARS-CoV-2. Your healthcare
provider will talk with you about what a positive serology test may mean for you based
on the kind of test that was used.
Q: If the serology test is positive and shows that I have antibodies to SARS-CoV-2, does
that mean I am immune to the virus?
A: Based on our knowledge of how the body reacts to an infection, we presume that the
presence of IgG antibodies could mean that you have some level of immunity to a virus.
However, at this time, it is unclear whether the presence of SARS-CoV-2 IgG antibodies
will result in immunity to prevent future COVID-19 infections. We will better understand
immunity to SARS-CoV-2 as we study what happens to people who test positive for
SARS-CoV-2 IgG antibodies and are again exposed to SARS-CoV-2, to determine if any
of them are confirmed to have new infections.
Q: If the serology test is positive and shows that I only have IgM antibodies to SARSCoV-2, does that mean I currently have COVID-19?
A: No, only a molecular diagnostic test can be used to determine the presence or
absence of the virus. Results from a serology test should not be used as the sole basis
for diagnosing if someone has or recently had COVID-19, but it can be used to screen
individuals who should receive molecular testing.