MOSCOW, March 21. /TASS/. At least 20% of citizens who have recovered from COVID-19 do not produce antibodies, Director of the Gamaleya National Research Institute of Epidemiology and Microbiology, the developer of the Sputnik V vaccine, Alexander Gintsburg announced on the Rossiya-1 TV channel.

"Among those who have been exposed to [coronavirus], these are good experimental data, at least 20% do not develop protective antibodies," the expert stated.

Gintsburg recommended that this population category was vaccinated against coronavirus to ensure the production of antibodies.

Speaking about the vaccines based on the same principle of genetic material delivery into cells as Sputnik V, Gintsburg noted that there was no reason to claim that they would be ineffective against new coronavirus strains.

Earlier, the Russian expert reported that about 20% of citizens infected with coronavirus failed to develop a sufficient amount of antibodies.

Since the start of the pandemic, about 122.9 mln people have been infected with COVID-19 worldwide, while over 2.7 mln have died. According to the crisis center, Russia registered a total of 4,456,869 COVID-19 cases, whereas some 4,069,395 people recovered and 95,030 died. Earlier, the country’s government set up an Internet hotline to keep the public updated on the coronavirus situation.