The research is published on the website of the University of Oxford.
In addition, according to a study by scientists, those who become infected with the coronavirus after receiving two shots of Pfizer or AstraZeneca vaccines may put others at greater risk of infection.
It is noted that 90 days after the second injection with drugs from Pfizer or AstraZeneca, their effectiveness against the delta strain decreases to 75% and 61%, respectively.
It clarifies that decreased efficiency is more common among people over 35 years old.
Earlier, the director of the Research Center for Epidemiology and Microbiology named after Gamaleya, Alexander Gintsburg, said that the employees of the center have a variant of the Sputnik V vaccine modified for the delta coronavirus strain.