This was stated by the Director of the National Research Center for Epidemiology and Microbiology named after N.F. Gamaleya of the Ministry of Health of the Russian Federation Alexander Ginzburg, writes TASS.
He said that the original version of the vaccine protected against coronavirus for the first two years. Since the emergence of variants Omicron 1, 2 and 3 (mid-summer 2022), the effectiveness of the vaccine has dropped eightfold, and when Omicron 4 and 5 were discovered, the effectiveness has already decreased by 20 times.
“And when the XBB.1.5 version of Omicron (Kraken) appeared – this was in January 2023 – Sputnik simply stopped protecting completely. Therefore, it was necessary to change the antigenic composition of the vaccine last summer,” Gintsburg clarified.
According to the scientist, the vaccine being developed to counter the “kraken” may be nasal. A person who is vaccinated in this way “ceases to be a carrier of the pathogen,” since such a vaccine breaks the chain of transmission of the virus.
