South Korea is facing a fresh challenge from COVID-19 variants.
The country on Monday reported 9 additional cases of mutated strains of coronavirus, bringing the total to 27.
Four of those cases were from the variant first detected in the UK, which is reportedly up to 1.7 times more transmissible.
Three of the cases were the South African variant, while the other two were Brazilian strain.
Seven of them were detected at the airport.
But two other patients tested positive during self-quarantine.
This new threat is emerging just as South Korea is seemingly bringing the third wave under control, and is preparing for the start of mass inoculation next month.
"The mutation of the virus is not something new, and the new variants are detected in a highly limited number of cases. But the problem is time. It is POSSIBLE that they mutate further to harm the effectiveness of the current vaccines, and spread on a national scale."
Studies show there is a chance that the current vaccines won't be fully effective against the South African strain.
And U.S. and British health authorities say the UK variant could be deadlier.
Meanwhile, South Korea has confirmed its first case of COVID-19 in a cat.
The kitten is suspected to have contracted the virus from its owners who stayed at a religious facility where a mass infection of over 100 cases broke out.
"There have been several cases of human to pet transmissions in other countries,.. but not the other way around"
Minks are so far the only animal that has been found to be able to transmit the virus to humans. But as a pre-emptive measure, the government is preparing guidelines for pet owners.
Lee Kyung-eun, Arirang News.