Estimated 647 Cases of COVID-19 Vaccine Breakthrough Infections... Janssen Accounts for More Than Half

Janssen 364 Cases · Pfizer 145 Cases · AZ 138 Cases
Janssen Estimated 32.0 Breakthrough Infections per 100,000 Cases

"Higher Vaccination in Younger Age Groups and Low Herd Immunity Influence"

Janssen COVID-19 Vaccine [Image source=Reuters Yonhap News]

[Asia Economy Reporter Lee Chun-hee] It has been revealed that there are 647 cases suspected to be 'breakthrough infections' where individuals contracted COVID-19 even after fulfilling all recommended doses of the COVID-19 vaccine and 14 days have passed. In particular, breakthrough infection cases after receiving the Janssen vaccine accounted for more than half, with 364 cases. However, health authorities stated that this is due to the characteristics of the vaccinated group rather than the vaccine itself, and no abnormal signs have been observed.

Park Young-jun, head of the epidemiological investigation team at the Central Disease Control Headquarters, said at the COVID-19 briefing on the 21st, "As of the 19th, analysis shows that out of about 5.4 million fully vaccinated individuals, 147 are estimated to have experienced breakthrough infections," adding, "This is about 12.0 cases per 100,000 vaccinations."

By vaccine type, Janssen vaccine recipients had the highest number of breakthrough infections at 364 cases. The breakthrough infection rate for Janssen was 32.0 cases per 100,000 vaccinations. This was followed by Pfizer with 145 cases and AstraZeneca (AZ) with 138 cases. Pfizer had 4.4 cases per 100,000 vaccinations, and AZ had 14.1 cases of COVID-19 infection per 100,000 vaccinations.

Health authorities attribute the notably high breakthrough infection rate of the Janssen vaccine more to the characteristics of the vaccinated population than to the vaccine itself. Park explained, "The Janssen vaccine was administered slightly more to younger age groups compared to other vaccines, and the relatively low herd immunity status may have influenced this," adding, "When looking at the transmission patterns of the COVID-19 virus, peer group transmission is the most common, and those with higher activity levels tend to spread it more."

Currently, health authorities classify cases confirmed positive for COVID-19 14 days after completing vaccination as 'suspected breakthrough infection cases,' and among these, cases confirmed to have been exposed to the virus after 14 days post-vaccination are classified as 'confirmed breakthrough infection cases.' However, Park noted, "We are not currently reporting confirmed cases separately." He explained, "As the number of breakthrough infections increases, it becomes difficult to verify the estimated exposure time for each individual case," and added, "Monitoring breakthrough infections is primarily to check for any abnormal signs, and for this purpose, statistics on suspected cases alone are sufficient."

The authorities currently report no significant abnormal signs related to breakthrough infections. Park stated, "We are mainly focusing on monitoring the scale, whether breakthrough infections increase over time after vaccination, and whether they are concentrated in specific age groups or populations." Since the breakthrough infection rate remains at a level of 10 to 30 cases per 100,000 vaccinations, which is still below 1%, he said, "If it reaches about 1 to 2%, it could be considered an abnormal sign, but currently, it is occurring at an extremely low level overall."

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