Russia denies lab accident after anti-plague researcher dies

Russian authorities say they found no evidence of a laboratory accident after a 28-year-old researcher at an anti-plague institute in Siberia died of severe pneumonia, while U.S. officials continue to monitor reports that she may have had pneumonic plague.

The woman, identified by Russian media as Darya Shipilova, worked at the Anti-Plague Institute of Siberia and the Far East in Irkutsk. The World Health Organization said she died overnight into Oct. 2, according to CBS News. Her cause of death has not been confirmed.

Irkutsk Governor Igor Kobzev described her illness as “pneumonia of undetermined etiology” and said no microorganisms connected to her work had been found in her biological samples, the BBC reported. Russia’s consumer and health watchdog, Rospotrebnadzor, said it had found no accident or emergency at the institute. It also said no pathogens causing dangerous infections had been found among nearly 200 people who had contact with Shipilova and were assessed as a precaution, according to CBS News.

Russian media initially reported that Shipilova broke a test tube containing plague bacteria in late September before falling ill, CBS News reported. Other unconfirmed accounts suggested she became ill after a trip to a region where plague occurs naturally among wild rodents, according to the BBC. The BBC reported that she had recently visited Buryatia, near the Mongolian border.

CBS News reported that Buryatia’s governor, Alexei Tsydenov, initially wrote in a state-backed messaging app that Shipilova had died of plague, then edited the post to say she had “possibly” died of it. Local officials also briefly posted a warning against visiting Shelekhov, where she was hospitalized, citing unofficial information about a human plague case, the outlet reported.

Kremlin spokesman Dmitry Peskov urged the public to rely on Rospotrebnadzor’s statements rather than rumors. Kobzev said no other institute staff had been reported to have sought medical attention since Shipilova’s death, according to the BBC.

U.S. Secretary of State Marco Rubio said officials were watching the case closely. “It seems that there was a worker at the lab that was infected,” he told reporters, while acknowledging limits on what U.S. officials knew. Rubio said the situation was not “cause for alarm,” but was “cause for focus.” The State Department said it was monitoring reports of a suspected fatal pneumonic plague case in coordination with the Centers for Disease Control and Prevention, NBC News reported. A WHO spokesperson said the apparent risk to the general public was low, based on unofficial information available, according to CBS News.

Plague is caused by the bacterium Yersinia pestis. Pneumonic plague, the rarest form, affects the lungs and can spread between people through respiratory droplets at close range. Symptoms can appear within one or two days of exposure, and rapid antibiotic treatment is critical, experts told NBC News.

Whether Shipilova had plague at all remains unknown. If she did, it is also unclear whether the infection came from bacteria studied in the laboratory or from a natural source.