MOSCOW, February 27. /TASS/. An increase in the number of coronavirus cases can occur for several years even after most of the population is vaccinated, Deputy Director for Clinical and Analytical Work at the Central Research Institute of Epidemiology Natalia Pshenichnaya told TASS.

"Even when most of the population is vaccinated, there will still be people who are susceptible to that infection, including due to a decrease in protective antibody titers. The epidemic spread of this infection will stop, but periodic rises in the incidence and outbreaks may persist for a number of years," she said.

According to Pshenichnaya, that was the case with Influenza A H1N1 2009. She noted that after the 2009 epidemic caused by this strain, a substantial increase in the swine flu incidence was recorded for several years. "Only in recent years, the annual registration of cases of influenza caused by that virus strain decreased," the expert stressed.

Mass vaccination against the novel coronavirus in Russia’s regions began on January 18. In order to develop herd immunity, 60% of the country’s adult population must be vaccinated.