ANTIBODY TESTING

WHAT IS ANTIBODY TESTING?

The antibody or serology test is done to ascertain a previous viral infection and the body’s immune response towards it. It screens antibodies, which are proteins in the blood produced by the immune system that combat infections such as viruses. Antibody testing may help avoid future occurrences of the same infection.

Antibodies are microorganism specific. For example, antibodies produced against the chickenpox virus may help to avoid a recurrence, but it will not protect from another viral infection such as influenza.

Antibody testing is extremely promising as it will help us to understand a selected virus’ widespread nature in our communities. The antibody tests determine whether or not a patient has been exposed to or can build up antibodies against it. Then it provides a transparent understanding of how widespread the virus is and tests the number of antibody types within the blood. These tests may identify those with immunity to the virus. Apposite antibody testing can enable health workers, first responders and our community to get back to work safely.

HOW IS THE ANTIBODY TEST DONE?

A phlebotomist or lab technician will take your blood sample through a vein in your forearm. The blood is sent to a lab where the blood is centrifuged and serum is tested for antibodies. The presence of antibodies specifies the body has an immunologic response to combat a specific viral disease.

The specific method used for antibody detection is called the ELISA technique (enzyme-linked immunosorbent assay) or CLIA technique (ChemiLuminescence Immuno Assay). Antibody tests provide details into a patient’s infection history for a particular disease. Two tests are implemented in antibody testing

• Test for total IgG and IgM
• Test for specific IgG.

WHO SHOULD GET TESTED?

Antibody tests are carried out in the following cases:

• As part of a clinical trial for first responders and health-care workers.
• In coalescence with diagnostic testing for patients, scheduled for a procedure or surgery.
• In setting a potential plasma donation with a previously diagnosed or suspected COVID-19.
• When no tests were performed despite the suspicion that the patient had a viral infection.
• In cases where a patient is suspected of having a viral infection, but despite a negative diagnostic test result, the doctor still thinks they had the disease and want to confirm it.
• In other cases, approved by a physician, such as when someone is in close contact with patients at high risk (elderly patients, patients with low immunity strength) and may have been previously exposed to the virus.

WHAT DOES AN ANTIBODY TEST RESULT MEAN? 

The expected time to get the antibody test results is 24 hours. The test results for an antibody will be reported either POSITIVE or NEGATIVE.

Positive Antibody Test Result

A positive antibody test result is likely to indicate that a person has developed an antibody response to a specific virus.

If you have a positive test result, you have recently or previously suffered from COVID infection or exposed to the virus. However, there is also a small chance of receiving a false positive test in case of being infected by another virus belonging to the same family (eg. Beta Coronavirus that cause the common cold).

Negative Antibody Test Result

A negative antibody test indicates that the antibodies to the virus were not detected in your sample. It could mean:

• You have not been previously infected with that particular disease.
• During the past, you acquired the disease, but your body did not produce or have not yet formed detectable antibodies. It is not clear whether all infected individuals produce a detectable antibody response.
• The result could also be wrong, referred to as a false negative. This happens when the test doesn’t detect antibodies despite the very fact that you just may have specific antibodies for that exact condition.

It should be noted that negative test results do not always convey the inference that you do not contain an antibody for a particular infection as there could be many other reasons to get a negative test. For example, if you get tested shortly after being infected with SARS-CoV-2, the test may be negative, as it takes time for the body to respond to an antibody. It is equally uncertain whether antibody levels decrease over time to undetectable levels.

WHERE SHOULD YOU GET AN ANTIBODY TESTING DONE?

You can get the antibody test done at your nearest Neuberg Diagnostic Lab.

The sample for testing can be collected at home or at lab by a phlebotomist.

Please note that this test is not for diagnosis of active COVID disease.