A researcher at a Russian institute researching plague and other pathogens in Siberia has died after developing pneumonia, prompting authorities to reportedly place nearly 200 other contacts under observation even as authorities in Russia pushed back against reports that the deceased researcher’s illness was caused by a laboratory incident.

According to Russia’s national public health agency Rospotrebnadzor , the researcher worked at the Irkutsk Anti-Plague Research Institute of Siberia and the Far East in Shelekhov and had contracted “pneumonia of unknown etiology.”

Independent regional outlet Liudi Baikala reported that the researcher was a 28-year-old woman who worked as a lab technician at the institute and her death prompted authorities to place nearly 200 people under observation at a hospital.

Igor Kobzev, the governor of Irkutsk, held an emergency meeting with regional anti-epidemic officials and the head of Rospotrebnadzor late last week, noting on Telegram that this was in response to a “suspected case of a particularly dangerous infection,” affecting a resident in the region.

Kobzev added that the public health agency had implemented a “comprehensive set of anti-epidemic measures.”

While Kobzev didn’t say what could have caused the “dangerous infection,” Alexey Tsydenov, the head of the neighboring region of Buryatia, said the woman “may have died of the plague,” while adding that there were no reported outbreaks in his region.

The Russian business outlet Kommersant also reported that authorities had implemented mask mandates at the Irkutsk Aluminum Smelter.

What Russia’s Top Health Authority Said About The Incident?

In a statement issued late Sunday, Rospotrebnadzor said the “sanitary and epidemiological situation” in Irkutsk and Shelekhov was “stable.” The agency said it conducted extensive testing and found no pathogens linked to the deceased patient’s laboratory work in her sample. The statement didn’t, however, specify if her pneumonia and death were caused by any other disease or how she may have contracted the illness. The statement, reported by state media agencies, added that no new cases of infectious disease have been reported among the plague institute’s employees in the past 10 days, and the institute also didn’t find any “emergency situations involving pathogenic microorganisms.” Testing of a deceased patient’s contacts revealed two cases of COVID-19 and two cases of rhinovirus infection, although it’s unclear if either were linked to the patient’s death.

What Is the Pneumonic Plague?

According to the World Health Organization, Plague is a disease caused by the zoonotic bacterium Yersinia pestis, which is usually found in small mammals like rodents and in their fleas. The Bubonic Plague is the most common form of plague, and it is transmitted from animals to humans through the bite of infected fleas. It can cause painful inflammation of the lymph node, called “buboes.” The less common Pneumonic Plague is far more virulent and can be transmitted through respiratory particles to other people; it can be highly fatal if not detected and treated early.

Both the identity and the source of the deceased researcher’s “pneumonia of unknown etiology” remain unclear. It’s also unknown whether she contracted any form of the plague or whether an incident occurred in the lab. Liudi Baikala reported that the woman accidentally broke a test tube containing the plague pathogen at the lab, although this has not been confirmed by Russian authorities.

On Sunday, Axios reported that the White House is monitoring reports about the death of the researcher and the subsequent emergency quarantine measures implemented by Russian authorities. An unnamed official from the Trump administration told the outlet that it is “ aware, monitoring the outbreak, and assessing options.” The president himself has not publicly commented on the matter.

Nearly 200 People Under Observation After Irkutsk Lab Worker Dies From Plague (The Moscow Times)

Researcher at Russian plague laboratory dies of ‘unknown’ infection (CNN)