The White House is monitoring reports of a suspected plague case in Russia, along with quarantines imposed after the death of a woman who worked at an anti-plague research facility, according to a Trump administration official who spoke to Axios on Sunday.

Russian health officials have responded to the death with precautionary measures but have not confirmed that the woman was infected with plague.

The Trump administration “is aware, monitoring the outbreak, and assessing options,” the administration official said.

The incident began Sept. 25, when 28-year-old Daria Shipilova, an employee at an anti-plague research institute in Russia’s Irkutsk region, reportedly broke a test tube containing the pathogen that causes pneumonic plague.

Shipilova was hospitalized four days later, on Sept. 29, suffering from severe pneumonia. She died overnight between Oct. 1 and Oct. 2.

Following her death, authorities ordered quarantines at several medical facilities in the region and placed nearly 200 people who had been in contact with Shipilova under medical observation.

Irkutsk Gov. Igor Kobzev said none of those under observation had developed symptoms and that their tests had come back negative.

Russian media have reported that Shipilova may have contracted pneumonic plague, but health officials have yet to confirm that diagnosis.

Russia’s public health agency said Shipilova suffered from “pneumonia of unknown etiology.” The agency added that subsequent testing detected no microorganisms associated with her work and said the region’s epidemiological situation remained stable.

Plague is a serious bacterial infection that can be life-threatening, but the disease is treatable with antibiotics when medical care is provided promptly, according to the Centers for Disease Control and Prevention.

White House spokespeople directed questions to the State Department. The State Department had not responded to a request for comment.