The U.S. Food and Drug Administration (FDA) has announced the approval for the first two coronavirus serology tests that detect an estimated quantity of antibodies present in your blood.

The tests, ADVIA Centaur COV2G and Attelica COV2G, developed by Siemens are called “semi-quantitative” tests, which means they do not show a precise measurement but they do estimate the number of antibodies produced against COVID-19, the infection caused by the virus.

Dr. Timothy Stenzel said, “Being able to measure a patient’s relative level of antibodies in response to a previous SARS-CoV-2 infection may be useful as we continue to learn more about the virus and what the existence of antibodies may mean.”

Dr. Stenzel is the director of the Office of In Vitro Diagnostics and Radiological Health in the FDA’s Center for Devices and Radiological Health.

“There are still many unknowns about what the presence of SARS-CoV-2 antibodies may tell us about potential immunity, but today’s authorizations give us additional tools to evaluate those antibodies as we continue to research and study this virus,” he continued.

“Patients should not interpret results as telling them they are immune, or have any level of immunity, from the virus.” Dr. Stenzel added. 

However, the FDA has warned patients against using the results from the tests as an indication to stop protecting themselves and others from the virus.

The agency recommends people to practice social distancing, use facemasks, and wash hands regularly, irrespective of the results they get from the tests.

The FDA has also warned patients that serology tests should not be used to diagnose an active infection. That’s because they only help with detecting antibodies the immune system develops in response to the coronavirus and not the virus itself.

Globally, COVID-19 has infected more than 17 million people and killed over 683,000 so far. In the United States, public health officials have reported more than 4 million confirmed cases of coronavirus, with over 156,000 deaths.