How are antibody tests different from conventional coronavirus tests?
By tests for coronavirus most often means PCR tests. They detect the release of the virus into the environment at the time of analysis. Those. determine whether a person poses a threat to others in terms of infection. For research, a smear from the oral cavity is taken from the patient. Biological material is examined for the presence of the genetic material of the virus – in this case, coronavirus.
PCR is considered one of the most accurate and sensitive methods for detecting infections. However, PCR tests for coronavirus sometimes give false positive or false negative results. For example, if the virus is released in a small amount, or the test system is not sensitive enough, or more than two weeks have passed since the onset of the disease.
Antibody assays are performed using other methods. In particular, for rapid diagnosis using the method of immunochromatographic analysis (IHA test). It is performed using a test strip or cassette on which a drop of blood is applied to the patient.
Such systems are easy to use and do not require special equipment. If no antibodies are detected, the test shows one bar; this is the internal quality control for each test. If there are IgM or IgG antibodies in the blood, then two or three.