A 29-year-old woman, Darya Shipilova, who worked at the Irkutsk Anti-plague Research Institute of Siberia and the Far East, died on the night of 2 October at a hospital in the nearby town of Shelekhov, two days after falling ill. Unconfirmed reports in Russian media suggest she may have been infected in a laboratory accident, but officials have not publicly confirmed that account.
Alexey Tsydenov, the head of the neighbouring Buryatia region, initially wrote on social media that she had died of plague, then edited his post to say she had "possibly" died of the disease. Rospotrebnadzor, Russia's health watchdog, said Shipilova died from "pneumonia of unknown aetiology" and that tests found no microorganisms linked to her professional work, describing the epidemiological situation as stable.
Despite the lack of a confirmed diagnosis, precautionary measures have been introduced across the region. According to reports from the US-funded Radio Free Europe/Radio Liberty, staff at the research institute have been isolated inside the facility since 2 October. Patients at Irkutsk city clinical hospital No 1 and the Ivano-Matreninskaya children's hospital said relatives were not being allowed to visit and people inside were not permitted to leave; only food and personal item deliveries are allowed. Local media also reported quarantine measures at hospitals No 3 and No 10, at least one maternity hospital, and a mask requirement at the Irkutsk aluminium smelter in Shelekhov.
Elena Trifonova, a journalist with the exiled Russian media outlet People of Baikal, said: "There are no obvious changes to daily life on the streets, but people are worried and anxious. Locals are angry that they are not being told anything." The plant director, Artyom Fominykh, described the mask requirement as a preventive measure, saying: "Better safe than sorry."