Following the call center outbreak in South Korea, a new study conducted by the Korean Centers for Disease Control and Prevention (KCDC) showed how easy it is to contract coronavirus in an office setting.
Out of 811 workers, 97 had contracted the virus — 94 of them sat on the 11th floor while 79 workers were in the same section.
How the virus spread on the 11th floor
On March 8, an agent on the said call center in Seoul tested positive for the virus. The employee, however, was working on the 10th floor and never went to the 11th floor.
As per South Korea’s standard protocol, officials closed the building the next day and ordered all workers to self-isolate for 14 days. All residents living on the 13th through the 18th floor was also asked to do home quarantine.
The skyscraper’s first 11 floors are commercial real estate, and the rest are residential apartments, which means possible contact could take place in the elevator and the lobby.
All workers and residents, along with their households, were tested. The government took a total of 1,143 swab samples that day.
However, only 97 came back positive with four presymptomatic patients. An additional 34 patients, who are all household members of the employees, contracted coronavirus as well.
But what took the KCDC’s attention was that the largest cluster of confirmed cases was found among workers who sat near one another. A total of 216 employees were working on the said floor, but only 94 fell ill, which means the virus’ attack rate is 43.5%.
Contact duration likely the main facilitator in coronavirus transmission
The Korean Centers for Disease Control and Prevention created a color-coded seating guide of employees working on the 11th floor.
In the diagram, the blue-colored desks specify the agents who contracted the virus. It revealed how offices’ inherent structure could easily spread the virus further, especially with long periods of interaction between employees.
The KCDC also emphasized how the duration of interaction played a vital role in spreading the virus further.
The institution notes:
“Despite considerable interaction between employees on different floors of the building in the elevators and lobby, the spread of COVID-19 was limited almost exclusively to the 11th floor, which means that the duration of interaction (or contact) was likely the main facilitator for further spreading.”
How South Korea mitigated the call center outbreak
Based on a report published by the South Korean government concerning the COVID-19 response strategy, the success in flattening the curve was due to three factors:
- mass testing
- contact tracing
- utilization of digital surveillance tools that allowed health officials to track down the virus
During the call center outbreak in Seoul last month, a team of government officials assigned to alert people sent more than five text messages — a total of 16, 000 messages — to anyone who came near the building during the outbreak period.
The initiative highlights how vital transparency is so that persons with potential exposure can immediately get themselves tested.
The KCDC also emphasized the urgency of mass testing and how it helped mitigate the situation by “disrupting transmission chains through isolation of symptomatic and asymptomatic COVID-19 patients.”
“Public health officials should conduct active surveillance and epidemiologic investigation in this quickly evolving landscape of COVID-19,” the KCDC added.
South Korea did not implement large-scale lockdowns as well, unlike the United States and countries in Europe.
Images courtesy of Sigre/Pixabay, The National Guard/Flickr, “Coronavirus Disease Outbreak in Call Center, South Korea,” KCDC