KDCA admits 'very high risk' for Covid nationwide

Vehicles wait at a drive-thru Covid-19 testing station in Goyang, Gyeonggi. [YONHAP]

Korea’s Covid-19 risk was “very high” over the past week, health authorities said, as the country continues to see an upward trend in pandemic indicators.

The Korea Disease Control and Prevention Agency (KDCA) announced Monday the results of its weekly virus risk assessment from Dec. 5 to 11 based on five-tiers — very low, low, medium, high and very high — using 17 indicators in three categories: medical and quarantine systems, Covid-19 outbreaks and vaccinations.

The risks levels for the country as a whole, the greater capital area and other regions were concluded to be very high, the KDCA said.

It was the first time the assessment for outside greater Seoul reached the highest level.

For the previous week from Nov. 28 to Dec. 4, the Covid-19 risk levels for the country and greater Seoul area were evaluated as very high, while other regions were at a medium risk level.

Korea reported 5,817 new Covid-19 infections on Monday, which was the highest tally for a Monday. It was up by 1,493, or 34.5 percent, from last Monday’s cases.

All but 34 were locally transmitted, bringing the total caseload to 523,088.

Covid-19 patients in critical condition numbered 876, remaining in the 800s for the sixth straight day.

Forty more people died of the virus, raising the death toll to 4,293. Of them, 21 were in their 80s or older, followed by 13 in their 70s, and four in their 60s.

“The Covid-19 risk factors for the overall country, the greater capital area, and non-capital areas were all evaluated as very high, and it is likely to lead to an increase in critical cases and fatalities next week,” the KDCA explained. It called for booster shots for everyone over 59 and full vaccinations of middle and high school students.

The country added 24 more cases of the new Omicron variant on Monday, confirming a total of 114 variant patients.

After analyzing the epidemiological characteristics of 123 cases of the Omicron strain (90 confirmed cases and 33 suspected cases), health officials said Monday that 24.4 percent of them were diagnosed with Omicron in an asymptomatic state. In other words, one in four Omicron patients was asymptomatic when confirmed.

Symptomatic patients suffered from fever, sore throat, and coughing as initial symptoms, and all are currently in mild conditions, the KDCA added.

There was no significant difference between patients who were not vaccinated and those who were.

For the Omicron variant, the time between infection of a primary case and a subsequent infection of a secondary case, known as “generation time,” was calculated as 2.8 to 3.4 days on average.

After analyzing transmission of 29 cases tied to a church in Incheon — where most of Korea’s Omicron cases came from — 26 people were infected in a space where three initial patients stayed for two to three hours on Nov. 28.

Considering the date of their onset symptoms, the generation time of the three people infected by the initial patient was 2.8 days. For the other 26 people who were later infected, it was 3.4 days.

This is shorter than the generation interval of 2.9 to 6.3 days of the Delta variant, which accounts for most new infections in Korea, adding evidence that transmission of the Omicron could be stronger than of Delta.

Starting Monday, reservations for booster shots opened to all adults over 17 who have passed at least three months since the final dose of their primary vaccination, while shots will start Wednesday.

With the rising number of breakthrough cases and worries over Omicron, the Defense Ministry brought forward the timeline for booster inoculations by two weeks, and began giving boosters to its troops on Monday.

BY SEO JI-EUN [seo.jieun1@joongang.co.kr]