Only one out of 3,055 South Koreans sampled for coronavirus antibody tests were found with immunity to the virus, health authorities said Thursday, though they downplayed the outcome given the samples lacking in representation and numbers.

The Korea Centers for Disease Control and Prevention announced the result of a  antibody test performed on 3,055 people -- 1,555 samples from the National Nutrition Survey and 1,500 from a medical institution in Seoul -- to see how many people had immunity against the COVID-19.  It was first such survey conducted in the country in an effort to grasp the actual scale of the virus‘ spread among local communities.

Only one person from the medical institution tested positive, which means only 0.03 percent of the people were immune to the virus.

“This indicates that we are not able to cope with the COVID-19 pandemic by developing herd immunity,” KCDC Deputy Director Kwon Joon-wook said.

It is difficult to estimate the degree of immunity in the country from the result, the KCDC stressed, as samples were not representative enough. None from Daegu and North Gyeongsang Province, two areas hit hardest by the country’s virus outbreak, were included, although the two represent  52.1 percent and 10.48 percent of the country’s total confirmed patients, respectively. 

The KCDC plans to test 3,300 more citizens living in Daegu and North Gyeogsang Province for antibodies in the coming months, with a plan to complete tests on 7,000 more by the end of this year.

Korea reported 50 new COVID-19 cases Thursday, pushing the country’s total caseload to 13,293.

Of the new cases, 28 were locally transmitted and the rest were imported from overseas.

As for locally transmitted cases, 15 were registered in Gwangju, which has become a new hotbed of the virus outbreak here. The new cases are traced to a marketing event which led to secondary transmission at a nursing home, a church and sauna.

Six cases were reported in Daejeon, four in Seoul, two in Incheon and one in Gyeonggi Province.

As Korea continues to see cases linked to small-scale church gatherings, the government has decided to put in place tightened social distancing rules at churches, effective from Friday. Under the new rules, any small gatherings outside regular worship services will be banned and all church visitors will have to register their identities through a QR code-based system before their entry.

Of the 22 imported cases, five people were detected during the quarantine screening process at the border and the rest while under home quarantine after arrival. Thirteen cases were from Asia, eight from the Americas and one from Africa.

So far, 12,019 people, or 90.4 percent, have been released from quarantine after making full recovery, up by 49 from a day earlier. Some 987 people are receiving medical treatment under quarantine.

Two more people died, bringing the death toll to 287. The overall fatality rate stands at 2.16 percent -- 2.65 percent for men and 1.78 percent for women. The rate is much higher for those in their 80s or over at 25.13 percent and those in their 70s at 9.36 percent.

The country has carried out 1,371,771 tests since Jan. 3, with 23,912 people awaiting results as of Thursday.

(laeticia.ock@heraldcorp.com)