A 28-year-old technician at a Russian plague research institute in Siberia died last week after falling ill with pneumonia, setting off fears of an outbreak that health officials in Geneva and Washington said this week was very unlikely to happen.
The woman, Daria Shipilova, worked at the Anti-Plague Research Institute outside Irkutsk. She was hospitalized in the nearby town of Shelekhov on Sept. 29, according to the independent regional outlet Lyudi Baikala, and died on Oct. 2, a friend told CNN. Rospotrebnadzor, Russia’s public health watchdog, said testing found “no microorganisms associated with the patient’s professional activities” and that she died of “pneumonia of unknown etiology.” The agency said it identified and monitored 197 of her contacts; two tested positive for COVID-19 and two for rhinovirus, and the rest showed no signs of infection.
Christian Lindmeier, a spokesman for the World Health Organization, told reporters in Geneva on Tuesday that the public health risk to the general population was very low. The U.S. Centers for Disease Control and Prevention said on X the same day that there was “no indication of a broader threat to the United States.” The episode was first detailed in English by Business Insider.
The reassurances sit against a tangle of unverified reports. The Moscow Times, an independent publication now based in Amsterdam, cited unconfirmed claims that Ms. Shipilova broke a test tube containing plague bacteria at the institute before she fell ill, and, citing the Russian Telegram channel Mash, that she was placed on a ventilator before dying. Radio Free Europe/Radio Liberty reported that the hospital that treated her was quarantined and her lab coworkers isolated. Russian authorities have not publicly confirmed either account.
“It’s an odd situation that needs more transparency,” Dr. Nahid Bhadelia, the founding director of the Boston University Center on Emerging Infectious Diseases, told Business Insider. If the test-tube account were true, she said, a chain of safety failures would have had to follow: a breach of protective equipment, no report of the incident, no preventive antibiotics, and an unmonitored trip to a district hospital. “The scenario, to me, doesn’t fit together,” she said.
Plague, caused by the bacterium Yersinia pestis, is rare now but still found in wild rodents and their fleas in many parts of the world. The pneumonic form, inhaled in infectious droplets, can bring symptoms in under 24 hours and is fatal if untreated. Caught early, it responds to a course of antibiotics. When an Arizona man died of pneumonic plague in July 2025 after contact with two sick cats, all 46 people exposed to him recovered after taking antibiotics. Person-to-person spread is rarer still; the last reported occurrence in the United States was in Los Angeles in 1924, according to Wired.
“We don’t know anything about anything right now,” said Gigi Gronvall, an immunologist and senior scholar at the Johns Hopkins Center for Health Security, who called the WHO’s low-risk finding correct. Geography helps, she said: “Siberia is not exactly Paris.” Dr. Rutul Dalal, an infectious disease physician at Penn State Health St. Joseph Medical Center, said that unlike COVID-19, plague has a ready treatment. “Here, we do have antibiotics to deal with this,” he said.
Kazakhstan, Kyrgyzstan, Uzbekistan and Tajikistan have nonetheless set up quarantine protocols, and Washington has urged Moscow to share what it knows. Some early Russian reports, including from the pro-Kremlin outlet REN TV, were inaccessible when Business Insider checked on Monday.
Even if the scare comes to nothing, the case lands in a period of unease about lab safety, as Vox reported. Fewer than 10 maximum-containment BSL4 labs existed worldwide in the late 1990s; by 2021 there were 59 in operation, under construction or planned, and 10 more had appeared by 2023, according to the Global BioLabs project. About 75 percent of operating BSL4 labs sit in cities, with at least 50,000 people within 2.5 miles, and no global body inspects or regulates them. “We are rolling back any progress we made post-Covid,” said Gregory Koblentz, a biosecurity scholar at George Mason University who co-founded the project.
Defenders of the research say plague remains endemic in Russia, which is why the Siberian institute exists at all. “The dangerous pathogens are there already,” Mr. Koblentz said. “How do you do it safely and securely?”