What Is the Pneumonic Plague and How Dangerous Is It?
The pulmonary infection is a severe disease caused by the bacterium Yersinia pestis when it enters the lungs.

TL;DR
- A Russian researcher at a plague laboratory has died.
- The U.S. State Department has called for more transparency from the Russian government.
- Russia has not confirmed if the worker died of plague, citing pneumonia of unknown origin.
- Russian officials told the WHO there are no plague cases in Irkutsk, where the worker died.