Even with two doses of the Pfizer vaccine, a study showed that the efficacy of preventing infection was only 22.5% for Omicron, a new mutation for COVID-19.
According to Bloomberg News, citing research from the African Health Institute in Durban, South Africa.
The African Institute of Health in South Africa analyzed plasma samples from 12 patients and found that the omicron mutation essentially reduced the vaccine's ability to protect against infection.
It is said that the level of neutralizing antibodies possessed by those who have completed the second dose of Pfizer vaccine is 41 times lower than that of the COVID-19 virus detected in China two years ago.
However, the researchers added that the vaccine's protective ability remains effective in severe disease cases.
In other words, vaccination significantly helps people with severe illness survive.
In addition, he emphasized that it was confirmed that the preventive effect against the Omicron mutation increased by 75% when receiving the booster vaccination, the so-called 'boost shot'.
Earlier, the British Health and Safety Administration also analyzed data from 581 omicron mutations and thousands of delta mutations, and found that the chance of preventing omicron mutation is 70-75% if you receive a booster vaccine.
However, in the study, those who received both doses of the AstraZeneca vaccine 25 weeks ago were only 40% less protective against the delta mutation and less than 10% with the omicron mutation.
In the case of the Pfizer vaccine, it was confirmed that 60% of people who completed the second dose were protected against the delta mutation and 40% against the omicron mutation.