Quantitative IgG antibody test for coronavirus 14.40

In 2-3 weeks after contracting the coronavirus SARS-CoV-2 infection, antiviral IgG type antibodies are formed in the blood, indicating the body’s response to the virus. Antibodies are similarly formed in the body as a result of vaccination. According to research, the antibodies are present in the body for at least six months.

The quantitative (QN) IgG antibody test for coronavirus not only determines the presence of antibodies, but also defines their precise numeric level in blood, which allows detecting the level of anti-coronavirus antibodies present in the body at the moment of giving the sample.

A positive antibody test result indicates that a person has either contracted and recovered from the infection caused by coronavirus SARS-CoV-2, has a late-stage COVID-19 disease or has developed antibodies due to vaccination.

It is recommended to take the quantitative IgG antibody test no sooner than three weeks after the onset of symptoms, a positive coronavirus test result or vaccination.

The IgG antibody test is not suitable for primary diagnosis of the disease; in case of a suspicion that a person may have the disease, a nasopharyngeal/pharyngeal washings PCR test should be taken.

Antibodies are detected from venous blood, which means that it is not necessary to abstain from eating and drinking beforehand.

You will receive the test result within 1 working day.

The result can be viewed in the digilugu.ee environment. It is necessary to log in with an ID card, Mobile ID or Smart-ID. It may also be accessible through other channels offered by your service provider. It is also possible to get a paper certificate from our blood collection points for a fee of 2€.

Reference values: < 50.0 AU/ml – negative
≥ 50.0 AU/ml – positive

A subsequent negative antibodies result does not preclude an initial positive test (PCR) result, as asymptomatic/mildly symptomatic people may not develop antibodies.

Interpretation of results:

  1. SARS coronavirus 2 IgG QN result is below the reference value

This means that there are not enough IgG antibodies against the coronavirus SARS-CoV-2 in the body to confirm that the patient has recovered from COVID-19 or to confirm the efficiency of vaccination. It cannot be excluded that the patient is in an early stage (weeks 1-2) of the disease, where antibodies have not yet formed. In addition, some people do not develop a measurable number of antibodies, e.g., patients who are asymptomatic, have only mild symptoms or immune deficiency. After recovering from the disease, the level of antibodies can decrease in time and this may also influence the test result. After vaccination, it may take weeks until antibodies are formed in blood.

  1. SARS coronavirus 2 IgG QN result is above the reference value

This means that IgG type antibodies against the coronavirus SARS-CoV-2 are present in the body, which indicates recent COVID-19 disease or formation of antibodies in the body after vaccination.


About the virus

Coronavirus SARS-CoV-2 causes a viral disease of the lower respiratory tract called COVID-19, the symptoms of which are fever, cough, and difficulty breathing, among others. The virus is known to primarily spread by infected droplets but can also be transmitted via contaminated surfaces. Symptoms usually appear within 14 days, but not all people develop symptoms. People who are infected but do not show any symptoms, are asymptomatic but can still spread the virus. The virus is particularly dangerous for the elderly and people suffering from chronic diseases as their immune system is weaker and may not cope as well as that of an average healthy person.

More information is available here.