Shipilova’s death has sparked speculation that a plague bacterium might have escaped from the Irkutsk Anti‑Plague Institute, but the Russian Ministry of Health has ruled out a link to the institute’s pathogens.
Officials placed roughly 200 people who had contact with Shipilova under observation, and a review of their health records has yet to reveal any confirmed cases of Yersinia pestis.
Experts such as Brendan Wren, a professor at the London School of Hygiene & Tropical Medicine, warned that pneumonic plague can be fatal within hours, yet he stressed that the absence of a lab incident makes infection unlikely.
Zania Stamataki, an associate professor at the University of Birmingham, explained that a broken test tube alone does not constitute exposure, and that containment protocols in high‑biosafety labs would trigger an incident report rather than an outbreak.
Investigators will now conduct a forensic analysis of Shipilova’s samples and the laboratory’s records to determine whether her illness stemmed from a lab mishap or an unrelated pathogen.