A staff member at a Siberian anti-plague research institute has died after contracting an infection that has not yet been identified, according to Forbes. The worker was based at the facility in Irkutsk, and dozens of colleagues have since been placed in quarantine, CNN reports.
The Moscow Times reports that close to 200 people are now under observation in connection with the case. Radio Free Europe/Radio Liberty says staff at the Siberian Anti-Plague Institute have been isolated following the death.
The case has drawn international attention. US Secretary of State Marco Rubio said Washington is closely monitoring the situation, describing the worker as having "possibly" died of plague, according to The Guardian.
The reporting so far leaves central questions unresolved. It is not clear whether the researcher's death was caused by plague or by another illness; Forbes has characterized the condition as an "unknown" pneumonia. No information has been released publicly about the worker's identity, the timeline of the illness, or the results of any laboratory testing. The number of people affected also remains described in varying terms across outlets, with CNN citing dozens in quarantine and The Moscow Times putting the figure under observation at nearly 200.
The institute where the death occurred specializes in plague research, which is why the case has prompted scrutiny beyond Russia's borders.
What to watch next: whether Russian authorities release test results identifying the pathogen, and whether additional cases emerge among the monitored contacts.
