Genomic Surveillance of SARS-CoV-2: Distribution of Clades in the Republic of Korea in 2020

Since a novel beta-coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first reported in December 2019, there has been a rapid global spread of the virus. Genomic surveillance was conducted on samples isolated from infected individuals to monitor the spread of genetic variants of SARS-CoV-2 in Korea. The Korea Disease Control and Prevention Agency performed whole genome sequencing of SARS-CoV-2 in Korea for 1 year (January 2020 to January 2021). A total of 2,488 SARSCoV-2 cases were sequenced (including 648 cases from abroad). Initially, the prevalent clades of SARSCoV-2 were the S and V clades, however, by March 2020, GH clade was the most dominant. Only international travelers were identified as having G or GR clades, and since the first variant 501Y.V1 was identified (from a traveler from the United Kingdom on December 22 nd , 2020), a total of 27 variants of 501Y.V1, 501Y.V2, and 484K.V2 have been classified (as of January 25 th , 2021). The results in this study indicated that quarantining of travelers entering Korea successfully prevented dissemination of the SARS-CoV-2 variants in Korea.

Identification of Coronavirus Isolated from a Patient in Korea with COVID-19

ObjectivesFollowing reports of patients with unexplained pneumonia at the end of December 2019 in Wuhan, China, the causative agent was identified as coronavirus (SARS-CoV-2), and the 2019 novel coronavirus disease was named COVID-19 by the World Health Organization. Putative patients with COVID-19 have been identified in South Korea, and attempts have been made to isolate the pathogen from these patients.MethodsUpper and lower respiratory tract secretion samples from putative patients with COVID-19 were inoculated onto cells to isolate the virus. Full genome sequencing and electron microscopy were used to identify the virus.ResultsThe virus replicated in Vero cells and cytopathic effects were observed. Full genome sequencing showed that the virus genome exhibited sequence homology of more than 99.9% with SARS-CoV-2 which was isolated from patients from other countries, for instance China. Sequence homology of SARS-CoV-2 with SARS-CoV, and MERS-CoV was 77.5% and 50%, respectively. Coronavirus-specific morphology was observed by electron microscopy in virus-infected Vero cells.ConclusionSARS-CoV-2 was isolated from putative patients with unexplained pneumonia and intermittent coughing and fever. The isolated virus was named BetaCoV/Korea/KCDC03/2020.

Viral Load Kinetics of SARS-CoV-2 Infection in First Two Patients in Korea

As of February 2020, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak started in China in December 2019 has been spreading in many countries in the world. With the numbers of confirmed cases are increasing, information on the epidemiologic investigation and clinical manifestation have been accumulated. However, data on viral load kinetics in confirmed cases are lacking. Here, we present the viral load kinetics of the first two confirmed patients with mild to moderate illnesses in Korea in whom distinct viral load kinetics are shown. This report suggests that viral load kinetics of SARS-CoV-2 may be different from that of previously reported other coronavirus infections such as SARS-CoV.

Viral Load Kinetics of SARS-CoV-2 Infection in First Two Patients in Korea

As of February 2020, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak started in China in December 2019 has been spreading in many countries in the world. With the numbers of confirmed cases are increasing, information on the epidemiologic investigation and clinical manifestation have been accumulated. However, data on viral load kinetics in confirmed cases are lacking. Here, we present the viral load kinetics of the first two confirmed patients with mild to moderate illnesses in Korea in whom distinct viral load kinetics are shown. This report suggests that viral load kinetics of SARS-CoV-2 may be different from that of previously reported other coronavirus infections such as SARS-CoV.

Viral Load Kinetics of SARS-CoV-2 Infection in First Two Patients in Korea

As of February 2020, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak started in China in December 2019 has been spreading in many countries in the world. With the numbers of confirmed cases are increasing, information on the epidemiologic investigation and clinical manifestation have been accumulated. However, data on viral load kinetics in confirmed cases are lacking. Here, we present the viral load kinetics of the first two confirmed patients with mild to moderate illnesses in Korea in whom distinct viral load kinetics are shown. This report suggests that viral load kinetics of SARS-CoV-2 may be different from that of previously reported other coronavirus infections such as SARS-CoV.