Director of the St. Petersburg Research Institute of Epidemiology and Microbiology named after Pasteur, Academician of the Russian Academy of Sciences Areg Totolyan announced this.

Earlier, he noted that approximately 15-20% of those who have recovered lose antibodies "in a month, one and a half, two months."

"A decrease in the level of antibodies does not mean the disappearance of immunity, since" memory cells "and cells that produce antibodies are formed, which must provide immune protection when they meet the virus again," the scientist explained, quoted by TASS.

Totolyan added that during asymptomatic course, antibodies are also produced, but they are unstable.

“In this regard, an extremely important question is the study of cellular immunity in these individuals and the search for an answer to the question - do they develop cellular immunity or not?

While experts are looking for an answer to this question, it is extremely important that all persons, regardless of whether they were sick or not, comply with the whole complex of measures for non-specific prevention of coronavirus infection: mask mode, social distance, hand treatment, and so on, ”he concluded.

Earlier, an immunologist, candidate of medical sciences Zoya Skorpileva, in an interview with URA.RU, assessed the effect of the asymptomatic form of COVID-19 on immunity.