Infection Reproduction Number Below 1 After 11 Weeks... "Recombinant Variant XE Requires Caution"

원본보기 아이콘

[Asia Economy Reporter Ki Ha-young] Last week, the infection reproduction number dropped below 1 for the first time in 11 weeks, indicating a decline in the Omicron wave. However, the nationwide COVID-19 risk level remained at the 'very high' stage, and caution is required regarding recombinant variants, making it difficult for health authorities to be optimistic about the situation.

According to the 'Weekly COVID-19 Risk Assessment Results' announced by the Central Disease Control Headquarters on the 5th, the infection reproduction number last week (March 27?April 2) was 0.91, falling below 1 for the first time in 11 weeks. The infection reproduction number is an indicator quantifying how many people one infected patient transmits the virus to. A value of 1 or higher means 'epidemic spread,' while below 1 means 'epidemic suppression.'

The number of new confirmed cases has also been declining since the third week of last month (March 13?19). Last week, the number of domestic confirmed cases was 2,142,503, with a weekly daily average of 306,072, a 12.9% decrease compared to the previous week.

However, the nationwide COVID-19 risk level has remained at the 'very high' stage for five consecutive weeks from the first week of March (February 27?March 5) through last week. This is due to the continued high burden on medical response, including intensive care unit beds.

The Quarantine and Medical Subcommittee of the Daily Recovery Support Committee also emphasized in its risk assessment that recombinant variants (XE) of Omicron BA.1 and BA.2 (Stealth Omicron) have been identified in Taiwan, Thailand, and the United Kingdom, and that the occurrence of these variants should be closely monitored. However, no XE variant infections have been confirmed domestically so far. Additionally, they stressed the need to strengthen management of nursing hospitals and facilities and actively use therapeutics to minimize deaths and severe cases.

In domestic infection cases, the detection rate of BA.2 was 67.7% as of last week, an increase of 11.4 percentage points from the previous week (56.3%). Among imported cases, 76.7% were also the BA.2 variant. BA.2, which has 1.3 to 1.5 times higher transmissibility than the existing BA.1, has rapidly increased in detection rate after becoming the dominant strain domestically the previous week.

Lee Sang-won, head of the Epidemiological Investigation and Analysis Team at the Central Disease Control Headquarters, said, "XE may have somewhat higher transmissibility than BA.2, but the number of cases is small, so there is a possibility of changes in the future, requiring additional monitoring and analysis. Although there have been no domestic occurrences of recombinant variants such as XE, additional investigations are planned as there is no global data analyzing the characteristics of these variants."

© The Asia Business Daily(www.asiae.co.kr). All rights reserved.