Russia Lab Worker's Death Raises Questions Over Possible Pneumonic Plague

The death of a 28-year-old woman who worked at an anti-plague laboratory in Russia has raised questions about the cause of her illness, although authorities have not confirmed that she died from plague.

Darya Shipilova, a 28-year-old worker at Russia's Irkutsk Anti-Plague Research Institute, died after developing severe pneumonia of undetermined cause. [Photo: Rocky Mountain Laboratories, NIAID, NIH]

The woman, identified by Russian media as Darya Shipilova, died on Oct. 2 after developing severe pneumonia. She worked at the Irkutsk Anti-Plague Research Institute of Siberia and the Far East.

The World Health Organization (WHO) said Russian authorities had reported that Shipilova died of pneumonia of undetermined cause and had not linked her illness to her work at the institute.

WHO said it had requested additional information, including laboratory test results and details about the health of people who had been in contact with her. About 200 contacts were placed under precautionary medical observation, according to WHO.

Russian authorities have said no recent case of plague had been reported in the Irkutsk region.

Reports have circulated that Shipilova may have been exposed to plague bacteria in a laboratory accident, but those reports have not been confirmed by Russian authorities.

Dr. Ashish Jha, the White House's former COVID-19 response coordinator, told NBC News that the possibility of biological-weapons programs in such laboratories would be particularly concerning and that more information was needed.

Plague is an infection caused by the bacterium Yersinia pestis.

The disease was responsible for the Black Death pandemic in the 14th century and has three main clinical forms: bubonic, pneumonic and septicemic plague.

Bubonic plague is the most common form and is typically transmitted through infected flea bites or contact with infected tissues. Pneumonic plague affects the lungs and can spread from person to person through respiratory droplets.

Untreated pneumonic and septicemic plague can be fatal, but antibiotics can be effective when treatment begins early.