This situation may sound eerily familiar. Last Friday, a woman in Siberia died of pneumonia of "unknown" origin, after possibly being exposed to the plague agent. Media in Russia reported that almost 200 people were quarantined. Officials quickly tried to allay concerns, but speculation and concerns are spreading online.

This situation may sound eerily familiar. Last Friday, a woman in Siberia died of pneumonia of "unknown" origin, after possibly being exposed to the plague agent. Media in Russia reported that almost 200 people were quarantined. Officials quickly tried to allay concerns, but speculation and concerns are spreading online.

The 28-year-old woman, Daria Shipilova, worked at the Anti-Pandemic Institute in the Irkutsk region of Siberia.

Unconfirmed reports suggested that he developed pneumonia-like symptoms after breaking a test tube containing plague bacteria, or fell ill after hiking in Buryatia on the Mongolian border. In this area there is an endemic epidemic among wild animals.

As of this date, Shipilova's cause of death has not been officially confirmed and laboratory tests are reportedly underway. But one thing is clear. Experts say this case is unlikely to lead to a global outbreak.