"After the 3rd inoculation, Omicron neutralizing antibody increases up to 29 times… Effect on mutation"

As a result of a survey of domestic COVID-19 vaccine recipients, it was found that after the third vaccination, the Omicron mutation defense ability was up to 29 times higher than when the primary vaccination was completed.

The National Institute of Infectious Diseases at the National Institutes of Health, as a result of a survey of 35 people who were vaccinated against COVID-19 between the ages of 20 and 59 in Korea, found that the ability to neutralize Omicron mutations increased 2 to 3 weeks after the third dose. ) said.

In the case of 15 patients who first completed the second dose with the AstraZeneca vaccine and then received the third dose with the Pfizer vaccine, the neutralizing antibody titer was 28.9 times higher than when the second dose was completed.

According to the Institute of Infectious Diseases, the neutralizing antibody value refers to the value of an antibody that prevents viral infection and induces a preventive effect.

The neutralizing antibody titer against Omicron mutation in 10 patients who received the 1st dose with AstraZeneca vaccine and 2nd and 3rd dose with Pfizer vaccine increased by 10.5 times, and 10 patients who received Pfizer vaccine three times increased by 17 times.

The third dose was found to be effective against both delta mutations and non-mutations.

In 10 people who received the first dose with AstraZeneca and the second and third doses with Pfizer vaccine, the neutralizing antibody titer to the delta mutation increased by 14.3 times and the antibody titer to the non-mutation increased by 9.9 times.

In 10 patients who received three doses of Pfizer, the neutralizing antibody titer to the delta mutation increased 21-fold, and the antibody titer to the non-mutant increased 7.8-fold.

However, this study has limitations in that only 35 people were surveyed, and those over the age of 60, who are considered vulnerable to infection, were not included.

At a briefing on the same day, Director Kwon Jun-wook of the National Institute of Health said, "If the sample size is large, meaningful results will come out in various ways, but at present, the need for rapid analysis is greater, so the neutralizing ability was judged as soon as the research subjects were secured. will," he replied.

Separately, the National Institute of Infectious Diseases reported that the antibody retention rate of 1,482 people (10-94 years old) who participated in the National Health and Nutrition Examination Survey from July to October last year was 67.1% (994 people).

Among the participants, the antibody retention rate of 1,114 vaccinated people was 70% after the first vaccination and 99.2% after completing the primary vaccination, and the antibody retention rate due to natural infection was 0.54% (8 patients).

In addition, 96.7% (9,567 people) of 9,896 blood donors (ages 20 to 59) who donated blood between November and December last year had antibodies to COVID-19, and the antibody retention rate due to natural infection rather than vaccination. was 1.2% (123 people).