The World Health Organization (WHO) has asked Russia for more information about the death of a 28-year-old laboratory worker at a Siberian research institute that studies plague, as authorities investigate the cause of her fatal pneumonia and seek to establish whether any infectious disease risk remains.
Darya Shipilova, who worked at the Irkutsk Anti-Plague Research Institute of Siberia and the Far East, died on Friday after developing severe pneumonia. Authorities have not established what caused the illness or how she became infected.
Her death prompted a public health response in the Irkutsk region, where around 200 people were placed in quarantine and senior health officials were sent to investigate. The measures were taken as authorities sought to determine whether Shipilova’s illness was linked to a dangerous pathogen.
Russia’s consumer health watchdog, Rospotrebnadzor, said almost 5,000 laboratory tests had found no dangerous pathogens among people who had contact with Shipilova. Around 90 per cent of those initially placed in quarantine had subsequently been released.
The agency also said Shipilova had been vaccinated against the dangerous infections she worked with at the institute. However, the vaccinations have not resolved the central question surrounding her death: what caused the pneumonia and how she contracted the illness.
WHO Director-General Tedros Adhanom Ghebreyesus said the organisation had requested additional information from Russian authorities about the cause of the pneumonia, the pathogen that led to the public health measures and reports concerning another institute employee who had developed pneumonia of undetermined origin.
“Timely, complete and transparent information sharing under the International Health Regulations is essential,” Tedros said in a statement published on X.
The WHO said Russian authorities had reported no recent cases of plague in the Irkutsk region. Based on the information available, the organisation assessed the risk as moderate to low within Irkutsk, low across Russia and very low across the wider WHO European region.
Russian officials also notified the WHO through an international health reporting system that tests had found no dangerous infectious disease pathogens among Shipilova’s contacts. The findings have helped inform the risk assessment, although the cause of her illness remains undetermined.
The Kremlin said Russia had followed established procedures in notifying the WHO. Kremlin spokesman Dmitry Peskov rejected reports surrounding the case and urged the public and media to rely on information provided by Rospotrebnadzor.
The investigation has attracted attention because the institute where Shipilova worked specialises in research into plague, a potentially fatal infectious disease. Pneumonic plague is a form of the disease that affects the lungs and can spread between people through respiratory particles. According to the WHO, symptoms can develop within as little as 24 hours of infection, making prompt diagnosis and treatment important. Antibiotics can be effective when treatment begins in time.
Despite the institute’s work and the public health measures introduced after Shipilova’s death, the available test results have not established that plague was involved in her illness. Russian authorities have reported no recent plague cases in the region, and the WHO’s assessment indicates a very low risk for the wider European region.
The case has also drawn interest from the United States, where officials have called for further information from Moscow. US President Donald Trump said on Tuesday that he expected to speak with Russian President Vladimir Putin about the case “very soon”.
Peskov said on Wednesday that no telephone conversation between the two presidents had been scheduled.
For the WHO, the immediate priority is to obtain enough information to clarify the cause of the illness, assess the reported case involving another institute employee and determine whether any further public health action is necessary. Until the cause is established, Shipilova’s death remains unexplained, even as initial testing has found no evidence of dangerous pathogens among her known contacts.
