"We do not yet have a complete picture of this case and cannot conduct a comprehensive risk assessment... Timely, thorough, and transparent information-sharing is critically essential to clarify conflicting accounts and ensure an accurate assessment of potential public risks," the WHO director-general stated.
Tedros revealed that the WHO has formally petitioned the Russian government for clarification regarding media reports of a second laboratory researcher hospitalized with pneumonia of undetermined etiology. The global health agency is currently awaiting an official response from Moscow.
Dr. Maria Van Kerkhove, WHO Director for Epidemic and Pandemic Threat Management, stressed that the organization remains unable to verify how the deceased lab worker contracted the pathogen or identify the specific viral or bacterial agent involved. If pneumonic plague has officially been ruled out by Russian authorities, "what did she actually die of?" Van Kerkhove noted.
Suspicious Lab Fatality in Siberia
Earlier reporting revealed the death of 28-year-old Daria Shipilova, a researcher at an anti-plague scientific research institute in Irkutsk Oblast. Eyewitness leaks indicate that on Sept. 25, Shipilova may have broken a laboratory vial containing live cultures of Yersinia pestis (the causative agent of pneumonic plague). She was hospitalized with severe acute pneumonia on Sept. 29 and died overnight into Oct. 2.
Russian authorities enforced strict containment measures across the research facility and neighboring medical clinics, isolating staff inside the buildings for three days. Approximately 200 close contacts were placed under active medical quarantine and monitoring.
Russian state authorities officially classified Shipilova's cause of death as "pneumonia of unknown origin," firmly denying any laboratory breach or plague diagnosis.
United States intelligence and public health entities — including the Centers for Disease Control and Prevention (CDC) and the Department of State — are actively examining the circumstances of the fatality and the subsequent hospital lockdowns in Siberia.
On Oct. 5, U.S. President Donald Trump described the development as "a big problem for Russia" and offered federal assistance, later announcing plans for a direct telephone call with Russian dictator Vladimir Putin to discuss the suspected plague emergency in Irkutsk Oblast.