Antibodies are produced by the immune system to identify and destroy harmful foreign substances (antigens), such as bacteria and viruses. The COVID-19 antibody test is done to detect the presence of antibodies in the blood that has been developed against coronavirus. A positive corona antibody test presumably means that a person was infected by coronavirus at some point in the past.
How does the antibody test works?
In the case of a novel coronavirus, a detectable antibody level in the blood can be achieved within one to two weeks post-infection. The basic method of coronavirus antibody test involves examining the binding of targeted antibodies to specific viral proteins. The platforms that are used for performing the tests include enzyme-linked immunosorbent assay (ELISA), chemiluminescent immunoassay, and lateral flow assay.
For the test, collected blood samples are incubated with the viral antigens on an assay platform. If the antibody against coronavirus is present in the blood, it will bind to the viral antigen, and a positive result will be obtained.
The viral antigens that are used to detect antibodies against coronaviruses include spike protein, nucleocapsid, and a receptor-binding domain.
The types of antibodies being detected via antibody tests include IgM (the first antibody to be produced upon infection), IgG (the most abundant antibody in the blood), and IgA (protects mucosa).
Benefits of the coronavirus antibody test: –
- Research suggests that many who are infected with COVID-19 show no or mild signs and symptoms of illness, so antibody tests could be useful in determining if you had it without knowing. Antibody test results could also help guide your doctor in making clinical decisions about your care.
- Widespread antibody testing could give researchers a better understanding of how many people have been infected and how deadly the virus is. Researchers can use this data to predict how COVID-19 might affect humans in the future, including why some people are more severely impacted than others.
- When a vaccine gets developed, it imitates an infection, and once injected, it helps build up the body’s natural defense against the infection, creating immunity to the disease. A part of that defense includes the production of antibodies. Testing is needed to verify the body’s response to a potential vaccine.
The antibody test can help survive millions of people from the novel coronavirus. The test has made the creation of vaccines and plasma therapy possible. It has a major contribution in saving many individuals from the pandemic.