"Domestic Omicron Cases Show No Severe or Fatal Outcomes, 60% Unvaccinated"

KDCA Analyzes 80 Early Infections
Clear Severe Disease Prevention Effect... Emphasizes Need for Vaccination

Omicron Rapid Test Kits Introduced from 30th
"Detects in 3-4 Hours"... Universal PCR Detects 5 Major Variants

[Image source=Yonhap News]

[Asia Economy Reporter Lee Chun-hee] Among domestic Omicron COVID-19 variant infections, there have been no severe cases or deaths, and about 60% of the infected are unvaccinated, according to an analysis. Amid growing controversy over whether existing vaccines can suppress Omicron, experts emphasize the need for vaccination, noting that although the vaccine's effectiveness in preventing infection may decrease due to the variant, its effectiveness in preventing severe illness remains clear.

On the 24th, according to the Korean Medical Association, the Korea Disease Control and Prevention Agency (KDCA), together with Korea University Anam Hospital and local governments in Seoul, Gyeonggi, and Incheon metropolitan areas, recently published a paper titled "Introduction and Transmission of the Omicron Variant in Korea in November 2021" in the Journal of Korean Medical Science (JKMS), analyzing 80 domestic Omicron variant cases from November 24 to December 10.

According to this paper, co-authored by Park Young-jun, head of the epidemiological investigation team at the Central Disease Control Headquarters, none of the infected individuals progressed to severe illness or death due to COVID-19. Among them, 27.5% (22 people) were asymptomatic, and most symptomatic cases were mild. Symptoms appeared in the order of sore throat (35.0%), cough (32.5%), fever (23.8%), and headache (23.8%).

The paper refers to this trend as the "trade-off hypothesis between virulence and transmissibility," suggesting that COVID-19 variants may evolve to have lower virulence but higher transmissibility. The generation time (interval between successive infections) for Omicron cases was 2.8 days, shorter than the previously most transmissible Delta variant's average of 2.9 to 6.3 days. Generation time is the period during which an infected person causes additional infections; the shorter this period, the faster the virus spreads.

The researchers evaluated that local transmission among unvaccinated individuals also contributed to Omicron's rapid spread. Of the 80 cases analyzed, 82.5% (66 people) were infected through community transmission, and among 78 individuals whose vaccination status was confirmed, 60% (48 people) were unvaccinated. In contrast, only 31.3% (25 people) were fully vaccinated. The researchers emphasized the need for further investigation, stating, "With the introduction of the Omicron variant, significant community transmission occurred among unvaccinated individuals," and stressed that "vaccination is necessary to prevent transmission."

Overseas studies also continue to report that although Omicron has high transmissibility, its virulence is low. On the 22nd (local time), researchers at Imperial College London announced that the risk of hospitalization due to Omicron infection is 40-45% lower than that of Delta. Notably, vaccinated individuals infected with Omicron had a lower risk of hospitalization compared to unvaccinated individuals.

Meanwhile, the KDCA announced that it has completed the development of a rapid gene amplification (PCR) test for quick identification of the Omicron variant and will distribute it to local governments starting on the 30th. This allows confirmation of Omicron within 3-4 hours after diagnosis, replacing the 3-5 days required for genome analysis. The test can detect Alpha, Beta, Gamma, Delta, and even stealth Omicron variants. It is the world's first PCR test capable of identifying five major variants in a single assay.

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