97% of the Population Has Antibodies, Yet... "Difficult to Consider as Herd Immunity"

On the 23rd, the government decided to fully lift the outdoor mask-wearing mandate starting from the 26th. Near Gongdeok Five-way Intersection in Mapo-gu, Seoul, office workers are seen walking without masks. Photo by Kang Jin-hyung aymsdream@

[Asia Economy Reporter Kim Young-won] Although 97% of the population was found to have antibodies against COVID-19, health authorities explained that "it is difficult to say that sufficient herd immunity has been formed."

On the 23rd, Kwon Jun-wook, director of the National Institute of Health at the Korea Disease Control and Prevention Agency, announced the results of an antibody positivity rate survey conducted on about 10,000 people across 17 cities and provinces nationwide, stating, "A high antibody positivity rate does not directly mean that the population has strong defense against the virus."

In this survey, the proportion of people possessing antibodies (S antibodies) through natural COVID-19 infection or vaccination was 97.38%. Following the resurgence last summer, the number of infected individuals increased, and vaccination rates continued to rise, resulting in the majority of the population having antibodies.

The reason authorities said that a high antibody positivity rate does not immediately translate into COVID-19 defense is that formed antibodies diminish over time. Director Kwon explained, "According to textbooks, antibodies last about 6 to 8 months after formation, and in the case of this coronavirus, it has been confirmed that they persist for more than 6 months."

When new variants emerge, the duration of antibody persistence becomes even shorter. Since vaccines developed so far were designed to respond to the initial strain of COVID-19, the antibodies formed through vaccination are also specific to the initial strain, and their defense against subsequent variants is reduced, Director Kwon added.

Furthermore, this survey only identified whether antibodies were present or not; it did not measure antibody levels or confirm the presence of neutralizing antibodies that can actually prevent COVID-19 infection. Among the 97.38% who have antibodies, there may be individuals whose antibody levels have nearly disappeared and who cannot prevent COVID-19 infection.

For this reason, health authorities emphasized that additional vaccination remains important despite the high antibody positivity rate. Director Kwon said, "For high-risk groups such as the elderly or those with underlying conditions, antibody formation rates are low and antibody duration is short, so additional vaccination is necessary after four months."

Professor Kim Dong-hyun of Hallym University College of Medicine, who participated in this survey, said, "Although vaccination rates are high, the fourth dose vaccination rate seems to be much lower compared to the third dose," adding, "As the effect of the third dose weakens, infections continue to occur despite high vaccination rates."

Health authorities believe that the fact that most of the population has antibodies will contribute more to preventing death or severe illness rather than infection itself. Director Kwon predicted, "Although the degree of immunity varies among individuals, since most people have antibodies, even if another outbreak occurs in the future, mortality and severe illness rates can be significantly reduced."

This content was produced with the assistance of AI translation services.