The White House is closely watching the situation in Russia’s Irkutsk region after the death of a woman who worked at an anti-plague research facility prompted quarantines and other precautionary measures.

A Trump administration official told Axios on Sunday that the White House is “aware, monitoring the outbreak, and assessing options.”

The woman, identified as 28-year-old Daria Shipilova, worked at the Irkutsk Anti-Plague Institute. Reports from Russian media said she may have accidentally broken a test tube containing live plague bacteria on Sept. 25. She developed severe pneumonia several days later, was hospitalized and died between Oct. 1 and Oct. 2.

Nearly 200 people who had contact with Shipilova have been placed under medical observation, with many hospitalized as a precaution. Regional officials have said those being monitored have shown no signs of illness and have tested negative so far.

Russian health authorities, however, have not confirmed that Shipilova had pneumonic plague. Russia’s public health agency, Rospotrebnadzor, said Sunday that she died from “pneumonia of unknown etiology” and that testing did not identify microorganisms connected to her work at the institute. The agency said the epidemiological situation in the region remains stable.

The suspected case has nevertheless triggered significant precautions, including hospital quarantines and additional monitoring in the region. Pneumonic plague is a serious bacterial infection that can spread through respiratory droplets, but it can be treated with antibiotics when detected and treated promptly.