The infectious disease specialist spoke about the timing of the formation of immunity after the flu shot

In order for the body to develop immunity to the flu, several weeks must pass from the moment of vaccination. This was announced to Izvestia on September 2 by Sergey Voznesensky, an infectious disease specialist and associate professor of the Department of Infectious Diseases at the Rudn University.

"It cannot be said that a person who has been vaccinated will be protected from influenza viruses tomorrow. It takes several weeks for the immune system to develop, and most often it takes almost a month after vaccination, when the immune system reaches its peak against the virus," he said.

Other factors may also cause infection after vaccination: a person may encounter another virus or pick up a strain of flu that is not included in the vaccine. At the same time, Voznesensky noted that vaccination is the only thing that significantly affects the reduction of morbidity.

The infectious disease specialist explained that a global influenza surveillance system operates under the auspices of the World Health Organization, with laboratories working within its framework to study the virus itself.

"Scientists around the world are deciding sometime in the spring which flu virus will enter the northern hemisphere in the autumn-winter period of this year. There is time for pharmaceutical companies to refine vaccines specifically for the variability that has occurred and the virus that is expected," Voznesensky said.

He stressed that over the decades of this system's existence, scientists have managed to significantly improve the quality of vaccines.

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On August 26, Rospotrebnadzor announced that the optimal time for flu vaccination is September and October for the successful formation of immune protection. According to Alexander Gorelov, Deputy Director for Scientific Work at the Central Research Institute of Epidemiology of Rospotrebnadzor, first of all, children, the elderly, citizens with chronic diseases and those who regularly come into contact with a large number of people are recommended to be vaccinated against influenza.