Only 55 of 17,890 people have antibodies against the novel coronavirus in South Korea, health authorities said Thursday, underscoring that the country's aggressive containment efforts might have curbed the prevalence of the virus.

The antibody rate of 0.31 percent in South Korea is extremely low compared with other nations and global cities, according to the Korea Disease Control and Prevention Agency (KDCA). Data from the World Health Organization shows that the rate is less than 10 percent in 398 regions in the world.

"This is a result that shows that our containment measures, such as social distancing and wearing masks, have been followed well compared to foreign countries," said Kwon Jun-wook, deputy director at KDCA. "But since there are also people with antibodies who had not been diagnosed before, we are aware that there are asymptomatic transmissions in the community."

Kwon added that results were based on serology tests conducted through Dec. 12, meaning they do not fully reflect the third wave of COVID-19 infections in the country.

Among 5,284 people who were tested through a nationwide health survey, five had coronavirus antibodies. Of the five, only three of them had tested positive for COVID-19, meaning the other two people resumed their daily activities while infected with the novel coronavirus.

Among 9,954 military cadets, 31 had coronavirus antibodies. Of them, 18 were undiagnosed people.

Health authorities also found that 19 people had developed antibodies in antibody tests on some 2,350 residents in Daegu and North Gyeongsang Province, as well as 302 medical personnel there.

The latest result indicated that herd immunity, which refers to a scenario where enough people in a community develop immunity to an infection so that the infection stops spreading, seems to be impossible in South Korea.

To better check the antibody rate in the country, health authorities said they plan to conduct serology tests on at least 32,000 people this year, including 5,000 workers at COVID-19 testing clinics and 15,000 military cadets.

Serology tests are used to figure out how many people have been infected with COVID-19 since antibodies are usually developed after people contract the virus. (Yonhap)