Suspected pneumonic plague in Siberia: What we know about the disease

Following the death of a Russian laboratory worker, there is speculation about an outbreak of pneumonic plague, a highly contagious bacterial infection of the lungs. Russia denies there is a broader risk to the community.

Russian officials have said the laboratory worker's death was not caused by a plague pathogen. The 28-year-old died of "pneumonia of unknown origin," according to Russia's Interfax news agency, citing Rospotrebnadzor, Russia's disease-control agency. According to that agency, samples taken from the woman showed no microorganisms "related to her professional activities." This contradicts earlier information.

Local media had previously reported that the woman, who worked at an institute dedicated to fighting plague, had dropped a test tube.

She reportedly died on Friday, October 2, 2026, at the district hospital in Shelekhov, a town near Irkutsk in Siberia.

According to official Russian figures, two hospitals and a children's clinic were placed under quarantine. Local reports said staff at the institute were being quarantined at their workplace. The US news site Axios has reported that around 200 people who had been in contact with the woman had been placed under observation. There were no further reported infections.

Even so, distrust of how Russia handles information persists. On one of DW's Russian-language social media channels, a user wrote: "It wouldn't surprise me if this turns into a disaster now, both in terms of the spread and the quarantine measures."

All that is known for certain, at time of writing and first publication (October 5, 2026), is that pneumonic plague is highly contagious.

Pneumonic plague is a form of plague that infects the lungs. Like every form of the disease, it is caused by Yersinia pestis , a bacterium usually found in small mammals, such as rodents and in the fleas that feed on them.