Anti SARS-Cov-2 serological test

Serological tests are not intended for diagnosing active COVID-19 infection. Diagnostic molecular (PCR) or antigen tests from a nasopharyngeal swab are exclusively used for that purpose. Similarly, serological tests cannot determine whether a person is contagious to their surroundings (household, coworkers, etc.). Diagnostic tests from a nasopharyngeal swab are also used for this purpose. The immune response to the SARS-Cov-2 virus is specific in that IgM and IgG antibodies appear almost simultaneously in the patient's blood 7-14 days after infection. Some individuals only develop IgA antibodies. Therefore, serological tests that provide separate results for IgM and IgG antibodies are not more useful than those that measure the total serological response (IgA+IgM+IgG). You need a serological test based on a doctor's recommendation as a supplement to a diagnostic test for coronavirus. If you have recovered from COVID-19, a positive result from this serological test means you have acquired immunity to the virus, which can be significant when returning to work. Since this test measures the titer (concentration) of antibodies to the S protein of the novel coronavirus, it allows you to monitor the dynamics, i.e., the change in the quantity of neutralizing antibodies over time. According to currently available data, most individuals reach the peak concentration of these antibodies by the 4th week after the onset of illness. After that, the antibody titer may plateau and gradually decline. The serological response, in terms of measured antibody concentration after recovering from a coronavirus infection, varies significantly among individuals. People who have recovered from COVID-19 without symptoms or with a mild form of the disease often have a lower titer of these antibodies compared to those who have recovered from a moderate or severe form of the disease, but this is not a rule. It is also assumed that individuals with a lower peak concentration of these antibodies may have a shorter serological response (and immune defense) compared to those with higher values. A serological test can check if you were infected with the novel coronavirus without symptoms (especially if you lived in close contact, e.g., in the same household or workplace, with a confirmed positive person) and if you had any contact with this virus during the pandemic. Neutralizing antibodies to the S protein of the novel coronavirus can also develop in vaccinated individuals. Therefore, this test can also be used to monitor the induced serological response after vaccination.

No special preparation is required. If you currently have symptoms of COVID-19 (fever, chills, cough, difficulty breathing), you should get a nasopharyngeal swab and a diagnostic antigen or PCR test.

For this test, blood is drawn from a vein. The test result is quantitative and represents the number or titer of antibodies in units per millilitre (U/ml). A measurement result of less than 0,4 U/ml is below the detection limit and is considered immeasurably low (negative). The cutoff value of 0,8 U/ml is used for result interpretation. An antibody titer measured below 0,8 U/ml is considered negative, while an antibody titer of 0,8 U/ml or higher is considered positive.

Test results are available on the same day.