MOSCOW, June 29. /TASS/. A third dose of the Sputnik V vaccine is safe, and it may provide a higher antibody titer than the one observed after the first two doses, says Gamaleya Research Institute Deputy Director Denis Logunov.

"Adenovirus vectors cannot multiply inside the human body, so administering them is far safer than contracting a disease. And, naturally, it is possible to administer the adenovirus vector repeatedly," he said. "There are some data from the foreign studies […] which indicate that the response after the third vaccination is even stronger than after the first two times," Logunov said. "The vaccination is tolerated safely, and the antibody titer becomes even higher than during the first two vaccinations."

He also noted that some people might have no response to the vaccination at all.

"A person can have an immunosuppression, some specific non-response to some vaccine component," Logunov concluded.

A total of 5,493,557 cases have been registered in Russia since the beginning of the pandemic, with 4,984,037 recoveries and 134,545 deaths.