The World Health Organization states it cannot assess the public health risk of a recent death in Russia because the country has not reported a confirmed cause. The UN health agency released a disease outbreak report over the weekend detailing the events surrounding the death of a Russian infectious disease researcher earlier this month. The WHO identified the lack of a confirmed etiological diagnosis as a "key uncertainty" that prevents an evaluation of whether Russian public health measures were adequate to prevent the spread of the unknown disease. The agency reported that it has seen no evidence of ongoing transmission of the mystery disease so far. However, the report notes that confidence in this assessment remains limited by the absence of a confirmed diagnosis and uncertainty regarding the source and mode of exposure. The WHO stated it first became aware of the death through media reports on October 2. The agency subsequently contacted Russian authorities to request information on October 3, 6, 7, and 8.