U.S. soldiers wearing face masks and gloves wielded thermometers instead of guns as the military fought to keep a deadly virus from spreading to this base in the middle of South Korea’s hardest-hit area.

South Korea reported another large jump in new virus cases Monday, according to The Associated Press. The 231 new cases brought South Korea's total to 833, and two more deaths raised its toll to seven.

The outbreak has spread rapidly since hitting the southeastern city of Daegu and surrounding areas last week, prompting growing concern for the local Army garrison with more than 9,000 American soldiers, family members and other personnel.