A group at Kitasato University conducted an experiment using cultured cells to see how effective the antibody of a person vaccinated in Japan was for the new coronavirus mutant virus "Omicron strain", and found that the vaccine was more effective than the Delta strain. It turns out that it has dropped significantly.
It has been pointed out that the efficacy of the vaccine for Omicron strains may be significantly reduced in previous reports overseas.
Regarding this, a group of Professor Kazuhiko Katayama of Kitasato University and others have shown how effective the antibody contained in the blood of 6 people each who received the Pfizer or Moderna vaccine twice in Japan using the actual Omicron strain. I investigated it by an experiment using cultured cells.
As a result, the values of neutralizing antibodies against the Omicron strain were on average 72% lower in those who had been vaccinated twice with Pfizer vaccine than in the Delta strain.
In addition, the value of neutralizing antibody against the Omicron strain in the person 3 months after inoculation with the Moderna vaccine was 82% lower on average than in the case of the Delta strain.
Professor Katayama said, "Because it is an experiment, I don't think that the effect of the vaccine will actually disappear at all, but it was confirmed that the effect on the Omicron strain has decreased even in Japan. The vaccine is given to the Omicron strain. Those who have done so also need to thoroughly implement basic infection control measures. "