COVID-19 Antibody (IgG), Immunoassay

This serology blood test identifies the presence of antibodies that indicate if a person had an immune response to COVID-19 (also known as coronavirus or SARS-CoV-2). A positive result to this antibody (IgG) test indicates that you may have had previous exposure to COVID-19 and your body has developed antibodies.

This blood test checks for a type of antibody called immunoglobulin G (IgG) that is the result of past or recent exposure to COVID-19, also known as the novel coronavirus (this is not a test for an active infection). The human body produces IgG antibodies as part of the immune response to the virus. It usually takes around 10 days to start producing enough antibodies to be detected in the blood. However, in some people it may take several weeks.

This is an antibody test used to detect the presence of antibodies indicating a immune system response to a past COVID-19 infection, not to diagnose active infections. Please follow up with your primary care physician or a local hospital for a COVID-19 diagnostic test if you believe you may have an active infection or if you are currently feeling sick.

Test results may help identify if you were previously exposed to the virus and, if exposed, can check whether or not your body has produced antibodies. Currently, the FDA supports antibody testing with the following important points:

• Antibody tests can play a critical role in the fight against COVID-19
• Testing can help identify who may have been exposed to SARS-CoV-2, the virus that causes the COVID-19 infection, and potentially developed an immune response
• Right now, it is unclear whether these individuals may be less susceptible to infection, but in the future, broad use of antibody tests and clinical follow-up will provide more information on this point

Multiple sources, including the CDC and healthcare experts, recommend you discuss your test results and whether to return to work with your healthcare provider and employer.

• If you were never diagnosed with COVID-19, this test can help determine if you may have been previously exposed to the virus.
• If you were diagnosed with COVID-19, this test can check whether or not your body has produced antibodies.

Although It may take up to 14 days after the onset of symptoms for antibodies to be developed within the body, 91% of people develop such antibodies within the first 8-13 days. Some people infected with COVID-19 will never exhibit symptoms but will have a detectable antibody response. While there is scientific belief that the presence of antibodies may provide immunity to future infections, data is still being gathered to state this conclusively.

This test may be helpful if you:

• Have had a positive test for COVID-19 and it has been at least 10 days and you want to know if you have detectable levels of IgG antibodies
• Have not experienced a fever or felt feverish in the last 3 days
• Have not experienced new or worsening symptoms of COVID-19 in the past 10 days: loss of smell or taste, shortness of breath or difficulty breathing, feeling weak or lethargic, lightheadedness or dizziness, vomiting or diarrhea, slurred speech, and/or seizures

This test may NOT be helpful if you are:

• Feeling sick or have had a fever within the last 3 full days, please contact a healthcare provider
• Trying to diagnose COVID-19, please contact a healthcare provider
• Less than 10 days since being tested for and diagnosed with COVID-19
• Directly exposed to COVID-19 in the past 14 days
• A person with a compromised immune system, a condition that makes it difficult to fight infections

This test does not require fasting and is only available for persons 18 years of age or older.