Last Friday, the 2nd of October, the first media reports emerged of a suspected case of pneumonic plague in a laboratory worker at the Irkutsk Antiplague Research Institute in the Russian Federation. The lab worker died after being hospitalized with severe pneumonia. Initial media reports suggested pneumonic plague following an accidental lab exposure. @WHO is aware that the Russian government held a meeting on the 2nd of October because they suspected a resident of the Irkutsk oblast had contracted a dangerous infection. On Saturday, WHO asked the Russian Federation for more information, in accordance with the International Health Regulations. On Tuesday, the Russian Federation responded, saying that no case of plague had recently been reported in the Irkutsk oblast, and that they had placed about 200 contacts in quarantine. However, WHO has requested further information on the laboratory tests conducted on the individual who died and the contacts, more detail on what prompted the public health measures, and details about the health status of the contacts. We have also sought verification of media reports of a second employee with pneumonia of undetermined cause. WHO has offered technical support related to plague and lab biosafety and biosecurity. As we don’t yet have the full picture of this event, we are not able to conduct a full risk assessment. Timely, complete and transparent information sharing under the International Health Regulations is essential to clarify conflicting reports and enable an accurate assessment of potential public health risks.