S. Korea discovers three new coronavirus strains from visitors from Pakistan and Uzbekistan

SEOUL -- South Korea's state anti-epidemic center has discovered three new strains of a novel coronavirus from inbound visitors from Pakistan and Uzbekistan through genetic sequencing and reported them to the World Health Organization for classification and reference by experts in other countries.

The Korea Centers for Disease Control and Prevention (KCDC), a state health watchdog, said it has identified three new variants of spike protein in COVID-19 viruses detected from inbound visitors from Pakistan and Uzbekistan. Genetic sequencing has been analyzed for 597 cases of domestic infection and 179 confirmed cases from abroad.

"We are conducting further analysis after reporting them to the WHO," KCDC director Jeong Eun-kyeong told a regular press briefing. KCDC officials said two new types came from Pakistan and one from Uzbekistan.

"Currently, there is no impact on polymerase chain reaction (PCR) diagnostic tests, but we believe that we need to review whether there are any changes in infectivity and pathogenicity," Jeong said. PCR is a molecular biology technique to amplify and detect DNA and RNA sequences. The real-time polymerase chain reaction (RT-PCR) method that amplifies specific DNA samples has been widely used in South Korea.

The WHO has classified the new coronavirus into different groups based on changes in amino acids caused by genetic sequencing differences. Lee Ki-eun, a KCDC analysis team leader, said that the new variants discovered in South Korea cannot be found in data stored in GISAID, which is a global science initiative and primary source for genomic data of influenza viruses and the novel coronavirus responsible for COVID-19.

"Since they are the first strains we've ever discovered, we need to do more of an evaluation with cells and animals to see what kind of infectivity they have and how they affect pathogenicity," Lee said, adding experts from around the world would have to monitor changes in virus genes.

So far, the new strains of SARS-CoV-2 have not caused any local infection because virus carriers from Pakistan and Uzbekistan were isolated upon arrival for obligatory self-quarantine for two weeks without contacting locals, Lee said.

South Korean health officials have sequenced genomes of COVID-19 patients to see if there are any mutations in a meaningful gene part. Medical saw mutations, which are important in the development of treatments and vaccines, as a process of evolution.