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SEOUL/BUSAN, July 24 (Yonhap) -- South Korea is considering adding Russia to a list of countries requiring stronger quarantine checks as cluster infections on Russian ships have continued to swell, health authorities said Friday.
At least 32 sailors on a Russia-flagged fishing vessel docked in the southeastern city of Busan tested positive for the new coronavirus earlier in the day, according to the Korea Centers for Disease Control and Prevention (KCDC).
Of 94 crewmembers aboard the 7,733-ton ship that entered a Busan port on July 8, 62 sailors tested negative for COVID-19.
With the newly identified cases, South Korea has detected 78 virus cases from eight Russian ships docked here since June.
"The government will consider designating Russia as a country subject to stricter quarantine steps," Yoon Tae-ho, a senior health official, told in a press briefing.
The government has placed six countries -- Bangladesh, Pakistan, Kazakhstan, Kyrgyzstan, the Philippines and Uzbekistan -- on the list of such high-risk countries in an effort to contain imported cases.
Arrivals from the countries are required to submit a certificate showing they tested negative for the new coronavirus.
Last month, 19 virus cases traced to two Russia-flagged ships decked in Busan were first reported, putting health authorities on higher alert over foreign ships-tied cluster infections.
Since late June, South Korea has been conducting on-board quarantine checks of foreign ships arriving from high-risk countries, after assessing the degree of risk.
The latest cluster infections tied to the Russian vessel came to light after a South Korean ship repairman, who had boarded the ship repeatedly for repair work, tested positive for the virus Thursday.
Health officials doubted that the person contracted the virus from the infected Russian sailors.
At least 20 people who have contacted the Korean worker are under close monitor.
Early this month, authorities carried out on-board quarantine checks of the ship, but there were reportedly no sailors showing virus symptoms at that time.