Health Authorities: "COVID-19 Infectiousness Increases from Early Symptom Onset" (Update)

Authorities Analyze Epidemiological Characteristics of 28 Domestic Patients
16 Imported Cases, 10 Domestic Infections... 2 Under Investigation
"Average Incubation Period 4.1 Days, No Asymptomatic Transmission but High Infectivity in Early Onset"

Jung Eun-kyung, Director of the Central Disease Control Headquarters, Korea Disease Control and Prevention Agency

[Asia Economy Reporter Choi Daeyeol] An analysis of domestic patients infected with the novel coronavirus (COVID-19) showed that the virus has high transmissibility, spreading rapidly even during the mild early stages of symptoms, according to South Korean health authorities.

On the 16th, the Central Disease Control Headquarters released an analysis of patients numbered 1 through 28 in South Korea. Among the 28 confirmed cases, 16 were imported cases. Of these, 12 were from China, the highest number, with one each from Japan and Thailand, and two from Singapore. The remaining 10 cases were infections transmitted domestically from existing patients.

Two cases still have unclear transmission routes. Patient number 18 had traveled to Thailand, but it remains uncertain whether the infection was contracted from exposure to the source there or from patient number 16, according to health authorities. Similarly, for patient number 28, it is unclear whether the infection was due to contact with patient number 3 or if it was contracted in China and developed after the incubation period.

Progress of COVID-19 Confirmed Cases

The initial clinical symptoms were mostly mild or nonspecific. The most common symptoms reported were mild fever and sore throat, each noted by nine patients. After hospitalization and imaging examinations, 18 patients?about two-thirds?were found to have pneumonia.

Analysis of the 10 domestic infection cases showed no evidence of secondary transmission during asymptomatic stages. Patients confirmed as secondarily infected domestically without travel to China were infected through close contact with family members or acquaintances. The average incubation period was identified as approximately 4.1 days. During a briefing, Director Jeong Eun-kyung stated, "Considering that most patients were heavily exposed on the first day of symptom onset and that those exposed on the first day were confirmed as secondary infections, we have reconfirmed that infectivity is high in the early stages of onset."

She added, "The virus can spread rapidly even when symptoms are mild, so while the condition may not be severe, the infectivity is high," and "Since infectivity exists from the early stage when it is relatively difficult to recognize patients, we assess that the risk of community transmission remains present."