Continued cluster infections of Covid-19 in greater Seoul led the number of testing at private institutions to exceed the level of massive tests earlier in Daegu conducted to trace the infection routes among members of a religious group, the government said.
Due to concerns over the demanding workload at testing laboratories and several false-positive cases, the health authorities decided to inspect testing labs jointly with the Korean Society for Laboratory Medicine (KSLM).
In a regular briefing on Monday, the Korea Centers for Disease Control and Prevention (KCDC) said a junior high school student and a high school student in Gwangju, who had tested positive for Covid-19, later tested negative in the second and third tests at the Gwangju Research Institute of Public Health and Environment.
A patient who tested positive in Seosan, South Chungcheong Province, also tested negative later.
An expert group of Covid-19 testing specialists concluded that the three persons were false-positive cases.
The KSLM said the three suspected patients tested false-positive due to “errors during the handling of the test samples.”
The KSLM’s on-site inspection revealed that one person handled the specimens of many people, which made the specimens vulnerable to contamination, although there was no problem in overall testing management.
The expert group worried that more Covid-19 tests incurred by the recent increase of confirmed cases in the Seoul metropolitan area could exhaust testers.
As of the last weekend, private medical institutions have conducted 2,083,750 tests for the past four to five months, according to the KSLM.
The maximum number of daily tests used to be about 24,000 when church-linked cluster infections rapidly rose in Daegu, but the current number is hitting over 36,000, it added.
KCDC said it would work with the KSLM to inspect testing laboratories.
“The false-positive cases are very important,” KCDC Director Jung Eun-kyeong said. “So far, we have focused on boosting testing capabilities. From now on, however, we will make more effort to secure test accuracy.”