The Chinese scientists made a conclusion that the level of the antibodies produced by the body after the Sinovac Biotech vaccine falls below the key threshold about six months after the second dose as Reuters reported.
The third vaccine can have a significant enhancing effect, according to scientists.
The Chinese researchers studied blood samples of healthy adults at the age of 18-59 from two groups; each of them had 50 members. People who received two doses in two and four weeks, only 16.9% and 35.2% of them respectively still had a level of neutralizing antibodies above the threshold six months after the second dose.
540 people got three doses.
The research showed that when the members in some groups received the third dose, six months after the second, the level of neutralizing antibodies increased three-five times 28 days after the inoculation in comparison with levels observed four weeks after the second dose.
The research did not check the action of antibodies against more transmitting variants of coronavirus.
As it was reported, people who have been fully vaccinated with Pfizer shot have about 10 times higher antibody concentrations than those who have received inactivated vaccines like China’s CoronaVac, according to a new study published in The Lancet.