Most of the 300-strong South Korean naval unit on an anti-piracy mission aboard a destroyer operating off the coast of East Africa is at risk of being infected with the novel coronavirus.

An additional 61 members of the Cheonghae unit have tested positive for COVID-19, bringing the total caseload on the 4,400-ton destroyer, Munmu the Great, to 68, military authorities here said Sunday.

The figure is expected to climb further, as the results of virus tests conducted on all the personnel Thursday continue to be disclosed in the coming days. So far the test results have been confirmed for 101 service members, according to the Joint Chiefs of Staff.

The cluster infection at the naval unit has revealed the indifference and negligence of military and government officials in preventing the mass outbreak of COVID-19 among the crew members. More keen attention should have been paid to antivirus measures for the crew members who have been kept in close proximity to each other in a closed space while staying together for months aboard the ship.

None of the Cheonghae unit members have been vaccinated as they left South Korea in February just before the country began its inoculation campaign.

So far, 72.6 percent of about 1,300 South Korean troops on overseas missions have been vaccinated. They got their vaccine doses before leaving here or in countries where they are stationed.

Service members of the Cheonghae unit have been a blind spot with regards to vaccination. According to the contract with foreign vaccine producers, vaccine doses sold to the country are supposed to be used only here and their shipment abroad are banned.

But a naval vessel is regarded as a sovereign territory under international law and there is no problem with sending vaccines to the Cheonghae unit members.

In April, Defense Minister Suh Wook made an instruction to strengthen and complement antivirus measures for naval vessels after 38 of the 84 crew members on a landing ship were confirmed to have been infected with COVID-19. In the same month, inoculation of military personnel began.

US President Joe Biden pledged to provide vaccines for all of the 550,000 South Korean troops during his summit talks with President Moon Jae-in at the White House in May.

Through the months, however, military and government officials gave no thought to vaccinating the Cheonghae unit members.

In a press conference during his trip to Europe in June, President Moon pledged to push for the provision of vaccines to North Korea if the isolated communist regime agreed to it. Some critics sarcastically note that he has been so preoccupied with the idea of providing vaccines to the North as to forget about sending them to South Korean naval members on an overseas mission.

Officials at Seoul’s Defense Ministry say they were concerned that there would be limited treatment for vaccination side effects that may occur aboard the ship. But they seem to be making an excuse for the failure to prevent the crew members from being exposed to the risk of mass infections with the virus.

The military should have ensured the vaccination of at least the crew members engaged in loading supplies at a port near the operating area of the ship.

With contact tracing under way, the coronavirus outbreak came after the vessel was docked at a nearby port for four days since June 28. A day after the ship left the port, a crew member, who had contacted locals in the process of loading supplies, reported symptoms related to COVID-19. He was just prescribed cold medicine without being put in isolation to get the virus test. In two weeks, seven were confirmed to have been infected with COVID-19 with many others complaining of pains symptomatic of the virus.

A thorough implementation of quarantine rules might have helped limit the spread of the virus among the crew members.

South Korea was scheduled to send two aerial refueling and transport planes later Sunday to bring all the crew members home as early as this week. The planes will also carry personnel to take over the ship and navigate it home.

Moon instructed the military Thursday to mobilize the aircraft “as speedily as possible.” The instruction might have sounded hollow to many people, who see him as being negligent in carrying out his duty as commander-in-chief.