Variants Challenge to Coronavirus Battle

Mutated strains of the new Coronavirus would be the key challenge to the country’s virus battle, and preventing the inflow of variants known to be more transmissible and resistant against vaccines.

This would be decisive in curbing the spread of COVID-19 as medical experts said on Thursday.

The country has continued to witness a rising number of COVID-19 variant cases, adding to concerns that the virus battle may be exacerbated by the more transmissible viruses.

As of Sunday, the country has reported 632 cases of highly transmissible new variants that were first identified in Brazil, South Africa and Britain.

The number of “emerging’’ variant cases totaled 473, according to the health authorities. So far, more than 30 cases of the Indian variant have been also reported.

“The rate of variant cases per daily new cases is expected to continue to rise,’’ Jeong Jae-hoon, a medical professor at Gachon University, told Yonhap News Agency, emphasising that the country’s antivirus efforts should prioritise screening entrants.

The daily rate of new variants out of all COVID-19 cases rose from 7.2 per cent during the first week of April to 14.8 per cent during the last week of April, the Korea Disease Control and Prevention Agency (KDCA) said.

Earlier this week, preemptive COVID-19 tests were advised in the southeastern city of Ulsan, which reported a sharp increase in the number of virus mutations.

Experts also feared that new variants of COVID-19 may be resistant to existing vaccines and treatments, added that some of them were known to be less effective in preventing transmission.

Jeong cited the latest study that shows the Pfizer vaccine effectively neutralised the British strain, but it was only one-sixth effective against variants from Brazil and South Africa.

Cheong Eum-mi, a medical professor at Ewha Womans University, also expressed concerns that the rising number of daily new variant cases would make achieving herd immunity more distant as fast-spreading COVID-19 variants can elude immune responses.

The country aims to create herd immunity by vaccinating 70 per cent of the population by November.

Herd immunity occurs when a large portion of the population becomes immune to a certain type of disease, making the spread of the disease from person to person unlikely.

South Korea has banned passenger flights arriving from Britain since Dec. 23, to block the new virus variant that was first identified there.

The country, however, lifted a ban on direct flights from Britain on a limited basis for the convenience of Korean residents living in the European nation.

In order to block the inflow of a new emerging strain from India, entrants from the country are mandatorily quarantined at state facilities for seven days before being put under self-quarantine depending on the results of virus tests.

Since late April, all entrants to South Korea, both foreigners and locals, must take preemptive polymerase chain reaction (PCR) tests upon their arrival.