Russia plague: What we know about the suspected case reportedly linked to a lab worker’s death

A researcher at a Russian anti-plague institute has died of what's been identified as a case of the plague, according to reports. Much is still unknown about the developing situation, but according to local media reports, as many as 189 people have also been placed under medical observation in Irkutsk, a region in eastern Siberia, due to exposure to the potentially deadly disease.What is the plague and how does it spread?Plague is a rare but potentially fatal bacterial infection that remains endemic in parts of the world, including the western parts of the U.S., but can be treated with antibiotics if identified quickly. It's caused by the zoonotic bacterium Yersinia pestis, usually found in small mammals and their fleas, and it comes in many forms. Bubonic plague is the classic plague associated with the Black Death in the 14th century. Without treatment, the bacteria can escape the lymphatic system and enter the bloodstream or lungs, leading to septicemic or pneumonic plague, according to the World Health Organization.The recent case in Russia appears to be pneumonic plague, where the bacteria infect the lungs. It can develop from another form of plague or by breathing in infectio...