[Exclusive] 'How Much Has Vaccine Immunity Dropped?'... Antibody Positivity Rate 2nd and 3rd Surveys Launched

Contracted with Korean Epidemiological Society last weekend
Assessing degree of immunity decline and social impact
Results expected late November to early December

[Image source=Yonhap News]

[Asia Economy Reporter Kim Young-won] Following the announcement of the first antibody positivity rate survey results conducted on approximately 10,000 citizens last September, the health authorities have commenced the second and third rounds of the survey.

An official from the Korea Disease Control and Prevention Agency (KDCA) stated on the 10th, "We finalized the service contract related to the second and third surveys last weekend." The Korean Society of Epidemiology will be responsible for the second and third surveys, just as it was for the first survey. The lead researcher remains the same, Professor Kim Dong-hyun from Hallym University College of Medicine.

The second antibody positivity rate survey will be a follow-up study, conducted only on those among the 9,959 participants of the first survey who wish to participate. The exact number of participants has not yet been finalized. For the third survey, new participants will be recruited.

This second survey will include additional questionnaire items, allowing analysis of the impact of social conditions as well as the level of immune decline. Professor Kim, who is overseeing the survey, said, "In the first survey, we calculated the S antibody titers," adding, "We will be able to examine the degree of immune decline based on how much the titers decrease." The questionnaire will include additional items such as occupational history and symptoms experienced during infection.

The first antibody positivity rate survey results, released on September 23, showed that among 9,901 citizens aged 5 and older, the N antibody positivity rate was 57.65%, and the S antibody positivity rate was 97.38%. This means that about 57% of the population has antibodies acquired through natural infection. Unlike the N antibody, which is formed only through natural infection, the S antibody can be produced through both natural infection and vaccination.

The impact of variants such as BA.5 is also expected to be identified through these additional surveys. When announcing the first survey results, Professor Kim explained, "By conducting the second and third surveys, we believe it will be possible to evaluate the additional impact caused by BA.5 that we are currently experiencing."

A KDCA official stated, "The results of the second survey are expected to be released between the end of this month and early December, and the third survey results are anticipated around January to February next year." Since the surveys are being conducted flexibly depending on the COVID-19 situation, the completion dates may change.

The health authorities plan to conduct antibody positivity rate surveys regularly next year as well. There is a plan under discussion to conduct periodic follow-up surveys every 3 to 4 months on participants from the first survey, while simultaneously recruiting some new participants to conduct the surveys in two stages.

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