What analyzes can confirm a person's complete recovery from COVID-19 and the absence of coronavirus in his body, said Sergey Netesov, doctor of biological sciences, virologist, in an interview with Sputnik radio. A negative PCR-test does not guarantee that a person who has undergone COVID-19 has fully recovered and his body is completely free of coronavirus, Sergei Netesov, Doctor of Biological Sciences, Professor, Head of the Biotechnology and Virology Laboratory of the Faculty of Natural Sciences of Novosibirsk State University, said in an interview with Sputnik radio. According to him, it is better to first take a sample from the nasopharynx, and then a blood test.
"If you give a guarantee of COVID-free (after an illness. - Ed.), You need to take PCR twice with an interval of, for example, three days. Another way is when PCR in the nasopharynx finally becomes negative, check PCR in the blood. This will be additional there is no guarantee that the coronavirus (in the body - Ed.) is gone", - said Sergey Netesov.
It is also advisable to check the level of antibodies. “The best thing is when the level of IgG antibodies is good and there are no IgM antibodies. This means that the acute infection has passed at least a month ago. If the IgM level is still high, it means that the virus may still be circulating. that a PCR sample taken from the nasopharynx determines the presence of a virus in the nasopharynx. From the nasopharynx, as you know, the virus leaves quite quickly: it can go into the lungs, into the blood, into the intestine. Then, if the virus is still circulating in the body, the formation of antibodies IgM class is stimulated by them", - Sergey Netesov explained.
At the same time, it is important not to forget about the risk of re-infection. Vaccination can drastically reduce the likelihood of illness and prevent the severe course of COVID-19.