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

the virus?

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.