WHO seeks Russian details on deaths at plague-control institute

The WHO cannot yet assess the risk. The organisation is seeking further information from Russia after reports of a possible second death from pneumonia in Irkutsk, where a young female scientist at the Institute for the Control of Plague Diseases had already died.

WHO expert Abdirahman Mahamud said in Geneva on October 8, 2026, that the report about the possible second death had been systematically checked and considered credible. Russian authorities have not responded to the organisation’s latest request for details.

The uncertainty has prevented the WHO from completing a comprehensive assessment of the situation. Director-General Tedros Adhanom Ghebreyesus said the organisation does not yet have a complete picture of what happened.

The case has drawn attention because the institute works in a field associated with plague surveillance and control. Russia has rejected suggestions that the scientist died from pneumonic plague. It has also said that no accident occurred at the institute. The available information leaves the WHO seeking laboratory, occupational and public-health details before it can determine whether the reports indicate an isolated medical event or a wider concern.

Russia has described the first death as pneumonia of unknown origin. The woman worked at the Institute for the Control of Plague Diseases in Irkutsk, in eastern Siberia. Russian authorities denied that she had pneumonic plague, a severe form of infection that can spread through respiratory droplets, according to the report cited by the WHO.

WHO specialist Maria van Kerkhove said the organisation has asked Russia to clarify the tests carried out on the woman and on around 200 other people. The WHO also wants to know precisely what materials she handled, what protective measures the institute used and whether she had been vaccinated.

Those details would help establish the possible route of exposure and whether other staff members faced a comparable risk. They would also allow international health officials to compare the event with known patterns of plague infection and other causes of pneumonia.

The WHO’s request covers both the clinical investigation and the institute’s operating conditions. Until Russian authorities provide the information, the organisation has limited grounds for drawing conclusions about transmission, exposure or the likelihood of additional cases.

Nearly 4,000 plague cases reached WHO surveillance systems between 2019 and 2025. The cases came from 10 countries, and 423 people died, figures that show why the organisation is seeking precise information when an unusual event is reported at a specialised institute.

The Irkutsk reports do not establish that plague caused either death. Russia has specifically rejected pneumonic plague as the cause of the scientist’s death, while the WHO continues to request evidence before completing its assessment. The distinction matters because pneumonia can result from many infections and non-infectious conditions, while pneumonic plague requires rapid investigation and treatment.

WHO officials said they routinely verify media reports before pursuing them with national authorities. Mahamud described the report of a possible second death as credible after that process. The organisation’s approach reflects standard disease surveillance: confirm the clinical facts, identify possible exposures, assess contacts and examine whether an incident could extend beyond the original location.

For countries such as Switzerland, which hosts the WHO headquarters in Geneva, the exchange illustrates how global health monitoring depends on timely national reporting and access to technical information.

The next assessment depends on Russia’s response. The WHO is waiting for information that could clarify what happened at the Irkutsk institute and whether anyone else faced an exposure risk. The requested material includes test results, laboratory procedures, protective measures and vaccination records.

The organisation has not announced a confirmed outbreak or identified pneumonic plague as the cause of the reported deaths. It has also not said that the incident poses a risk to Switzerland or other countries. Its public position remains limited to the absence of sufficient information for a comprehensive risk assessment.

That restraint is significant for health authorities and the public. A credible media report can trigger international enquiries, but it cannot replace clinical records, laboratory findings or an investigation of possible contacts. The WHO needs those elements to distinguish an isolated illness from an event requiring broader action.

In Geneva, where the WHO coordinates much of the world’s disease surveillance, officials will continue to seek clarification from Russian counterparts. Until then, the Irkutsk reports remain under investigation, with the available evidence pointing to pneumonia of unknown origin and no confirmed case of pneumonic plague.