The US is monitoring a possible pneumonic plague case in Russia after a 28-year-old lab worker died.

• US monitors possible pneumonic plague case in Siberia
• Nearly 200 people are under surveillance
• Russia has not confirmed the plague.

Pneumonic plague. The United States is closely monitoring the health situation in Irkutsk, Siberia, after the death of a 28-year-old lab worker at a specialized institute for infectious diseases.

Although reports have raised the possibility of a pneumonic plague case, Russian authorities have not confirmed that the disease caused her death.

Pneumonic Plague: US Closely Follows Developments in Russia

US Secretary of State Marco Rubio said on October 5 that Washington is closely following reports from Russia, while stressing that there is no reason for alarm at this time.

«We are monitoring and following it closely. I don’t think it’s a cause for alarm, but rather for attention and surveillance,» Rubio told journalists, according to Reuters.

The official also emphasized the importance of monitoring such situations because infectious diseases can spread rapidly.

Lab Worker Dies After Developing Pneumonia

🔴There is an alert for suspected pneumonic plague: Russian hospitals are under quarantine.

The death of Daria Shipilova, a 28-year-old woman, from a suspected case of pneumonic plague forced five hospitals in the Russian region of Irkutsk to go into quarantine.

Preliminary information suggests that her death may have been caused by the Yersinia pestis bacteria, which can be transmitted between people through respiratory secretions.

— EL TIEMPO (@ELTIEMPO) October 5, 2026

The deceased was identified by Infobae as Daria Shipilova, a 28-year-old employee of the Irkutsk Anti-Plague Institute, which studies highly dangerous infectious agents.

The woman developed a severe respiratory illness, was hospitalized, and later died. N+ reported that her death occurred on October 2.

Russian authorities have said the cause of her death remains under investigation. Irkutsk Governor Igor Kobzev described the condition as «pneumonia of unknown origin.»

Nearly 200 People Under Surveillance Over Possible Pneumonic Plague in Russia

Secretary of State Marco Rubio said the United States is closely monitoring reports of a suspected pneumonic plague case in Russia. The reports follow the death of 28-year-old Daria Shipilova, an employee of a plague research institute in the Siberian city of Irkutsk, about 2,600 miles east of Moscow. Russian media have reported that hospitals were quarantined and dozens of people placed under observation after her death, although those reports have not been confirmed by Russian authorities.

— Newsweek (@Newsweek) October 5, 2026

Infobae reported that nearly 200 people who may have had contact with Daria Shipilova were identified and placed under medical surveillance while the investigation continues.

Several hospitals in the region also adopted preventive restrictions. Infobae reported that five medical centers were placed under quarantine for approximately three weeks.

An aluminum plant in Shelekhov also made masks mandatory for employees as a preventive measure.

Possible Laboratory Exposure Under Investigation

One version circulating publicly claims that Daria Shipilova accidentally broke a test tube containing material with the Yersinia pestis bacteria while working.

However, Infobae notes that authorities have not confirmed that such an incident occurred or that it was the route of any possible exposure.

Rospotrebnadzor reported that testing did not detect microorganisms related to the woman’s work activities or evidence of an accident involving the handling of pathogens.

Europe Is Also Monitoring the Situation

The European Commission is also closely following developments and is in contact with the European Centre for Disease Prevention and Control, according to information gathered by El Confidencial.

«Public health is a priority,» said Eva Hrncirova, the European Commission’s Health Spokesperson, who emphasized the importance of having reliable epidemiological and laboratory information.

The Kremlin, meanwhile, called for avoiding speculation. Spokesperson Dmitry Peskov urged people «not to pay attention to rumors about a plague outbreak» and to rely on information from Rospotrebnadzor.

What Is Pneumonic Plague?

Pneumonic plague is an infection caused by the Yersinia pestis bacteria that directly affects the lungs and can spread from person to person through respiratory particles or secretions.

N+ and Infobae note that despite its severity, it can be treated with antibiotics when detected early. So far, Russian authorities say no new cases linked to the institute have been identified.