A research station in Antarctica is battling a COVID-19 outbreak despite being located in one of the most remote corners of the world.

Since mid-December, 11 of the 33 workers at Belgium’s Princess Elisabeth Polar Station have tested positive for the virus.

Joseph Cheek, a project manager for the International Polar Foundation, which manages the outpost, told ABC News that the first case was reported on Dec. 15 in a worker who had traveled to Antarctica with a group via South Africa despite strict testing and travel requirements.

Before arriving in South Africa from their country of origin, the workers were required to have a negative PCR test at least 72 hours prior to the flight. The employees then had to quarantine in South Africa for 10 days and take another PCR test five days into the quarantine period.

Once the quarantine period was over, each person was required to take another test 48 hours before their flight to Antarctica and five days after arrival.

It was on the sixth day after arrival that the first worker tested positive followed by two more workers.

The three patients were evacuated on Dec. 23 but, following their departure, an additional eight people were confirmed to have the virus.

The workers had all been fully vaccinated against COVID-19 with at least one having received a booster shot.

Cheek said all the cases have been mild and there are currently no cases at the Princess Elizabeth station.

“No one who caught COVID at the station had any severe symptoms,” he said. “Everyone recovered quickly. Symptoms experienced by those infected included a sore throat primarily, sometimes a mild fever, slight fatigue and on occasion a headache lasting for one to three days.”

There were two emergency doctors on site with equipment necessary to treat patients if their symptoms become severe, but Cheek said the physicians determined that no treatments were necessary beyond quarantine and rest.

All of the scientists at the station were given the option to evacuate on a flight scheduled for Jan. 12 but they decided to stay to continue their research, according to Cheek.

“The outbreak has only been a minor nuisance and everyone who had previously tested positive and had to quarantine is now back to work,” he said.

Cheek added that the IPF and the Belgian Polar Secretariat are currently collecting data on the origins of the outbreak, but cannot determine if they were infected with the highly transmissible omicron variant, which makes up 99% of all COVID cases in South Africa.

This is not the first time that a COVID-19 outbreak has been reported in Antarctica.

In December 2020, Chile announced that 36 cases of the virus had been confirmed at its Bernardo O’Higgins research station on the Antarctic Peninsula.

Despite Antarctica’s remote location, research and military stations have taken strict measures to prevent the spread of COVID-19, including limiting the number of tourists and locking down bases.