'Immune Evasion' BA.5 Becomes Dominant Strain...Domestic Infection Detection Rate 60.9% (Update)

Domestic infection 60.9%, Overseas inflow 79.4%
Combined detection rate 66.8%

[Image source=Yonhap News]

[Asia Economy Reporter Kim Young-won] BA.5, known to have a faster transmission rate and immune evasion ability than the Omicron variant, has become the dominant strain in South Korea.

According to the Central Disease Control Headquarters on the 2nd, the detection rate of domestically infected BA.5 from June 24 to 30 was 60.9%, an increase of 11.8 percentage points from the previous week (49.1%). Authorities consider a variant to be dominant when its domestic detection rate exceeds 50%.

The detection rate of imported BA.5 cases also increased. During the same period, it rose by 6.1 percentage points from 73.3% to 79.4%, resulting in an overall detection rate combining domestic and imported cases of 56.3% to 66.8%.

BA.5 became the dominant strain 11 weeks after the first confirmed domestic case on May 12. The Delta variant took 14 weeks to become dominant after the first domestic infection was confirmed on April 29 last year, and Omicron (BA.1 variant) took 8 weeks after the first confirmed infection on December 1 last year.

Health authorities analyzed that BA.5 spreads rapidly due to its higher immune evasion ability compared to previous variants. However, no significant differences have been found in severity or symptoms so far. Im Sook-young, head of the Central Disease Control Headquarters' situation management team, said, "Since the clinical symptoms are from a subvariant of Omicron, we believe they are similar to Omicron," adding, "We will continue to monitor and assess differences in severity and clinical symptoms."

During the past week (July 24?30), additional detected variant cases were 1,117 for BA.5, 46 for BA.2.12.1, 45 for BA.4, and 5 for BA.2.75.

The combined detection rates of variants other than BA.5, including domestic and imported cases, were ▲BA.2.3 5.0%, ▲BA.2.12.1 2.8%, and ▲BA.4 2.7%.

BA.2.75, which has 8 more spike gene mutations than BA.2 and is known for strong immune evasion and high transmissibility, attracted attention but has not occurred as much as initially feared in South Korea.

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