Omicron, at least 272 close contacts including family and acquaintances... Concerns over 'n-th generation infections'

On the 1st, officials at Incheon Airport are guiding people to the COVID-19 testing center. [Image source=Yonhap News]

[Asia Economy Reporter Yoo Hyun-seok] As COVID-19 variant 'Omicron' infections have been consecutively confirmed, there are growing concerns about chain transmission.

According to the quarantine authorities on the 2nd, a total of 5 Omicron variant infections have been finally confirmed in South Korea so far. Among them, 3 are a couple in their 40s, Mr. A and his spouse, who visited Nigeria, and a 30-year-old acquaintance, Mr. B. The remaining 2 are other overseas entrants confirmed positive after traveling to Nigeria.

The couple, Mr. A and his spouse, visited Nigeria from the 14th to the 23rd of last month and returned on the 24th. They were diagnosed with COVID-19 on the very next day, the 25th.

Since the couple had completed vaccination with the Moderna vaccine and were exempt from quarantine, they did not face any particular restrictions on external activities or movements for one day after entry until their positive diagnosis was confirmed. Four days later, on the 29th of last month, Mr. B, who traveled with the couple from the airport to their home upon their arrival, tested positive, followed by one of the couple’s teenage children living with them on the 30th.

Mr. B is unvaccinated. According to quarantine guidelines, he should have been classified as a close contact and entered self-quarantine after the couple’s positive diagnosis on the 25th of last month.

However, it was revealed that the quarantine and diagnostic testing for Mr. B were delayed because the couple gave false statements during the initial epidemiological investigation. As a result, there was a four-day gap between the couple’s diagnosis and Mr. B’s diagnosis, during which Mr. B visited nearby restaurants, markets, a dental clinic, and even attended a church program with about 400 attendees.

Park Young-jun, head of the epidemiological investigation team at the Central Disease Control Headquarters, explained, "During the initial epidemiological investigation of the confirmed couple, the contact with the acquaintance was omitted, but contact was confirmed during a subsequent re-investigation. If clear violations are confirmed through fact verification, the relevant local government will take legal action under the Infectious Disease Control and Prevention Act."

The number of officially confirmed contacts by the authorities has already reached about 270.

Among them, 43 people who boarded the same flight as the couple, and 53 people who had contact at their home or residence facilities. The contacts of Mr. B’s wife, mother-in-law, and acquaintance include another 79 family members, acquaintances, and work-related persons. Therefore, depending on the test results of Mr. B’s wife, mother-in-law, and acquaintance, the final number of infected people may increase.

The authorities are proactively conducting contact investigations not only for infected individuals but also for their family members, coworkers, and acquaintances suspected of infection.

If additional confirmed cases emerge here, it is highly likely that chain infections beyond the third generation are occurring, as the third-generation infection has already progressed involving Mr. A and his spouse, Mr. B, and Mr. B’s family.

Meanwhile, the couple’s son tested positive during self-quarantine, and it has been confirmed that there were no additional contacts in the local community. The son’s Omicron variant infection status is expected to be announced late this afternoon.

The couple’s other child, a daughter, tested negative for COVID-19 and is currently quarantining at home. However, considering the virus incubation period, she may test positive in a subsequent retest.

The infection cluster centered on two women in their 50s, whose Omicron infections were confirmed the day before, is also in an unstable state. These women, residing in Gyeonggi Province, visited Nigeria from the 13th to the 22nd of last month and entered the country on the 23rd. They tested positive for COVID-19 during self-quarantine on the 24th, one day after entry. Neither of them had been vaccinated. They are currently receiving home treatment in Gyeonggi Province.

Since they were diagnosed positive one day after entry and began isolation treatment, there were no additional close contacts except for one family member who assisted their movement upon arrival.

However, a total of 139 passengers used the same flight as them, and among these, two tested positive. However, these were confirmed to be infections with the Delta variant.

It is also concerning that all confirmed and suspected Omicron variant infections so far have been concentrated in the densely populated Seoul metropolitan area. Considering the scale of contacts of confirmed cases, the authorities are strengthening responses while keeping open the possibility that the Omicron variant has spread beyond the metropolitan area to non-metropolitan regions.