Black Death bacteria thought to be extinct

 The type of bacteria which caused the European "Black Death" plague in the mid-1300s has been identified as Yersina pestis, according to a news report on CNN.com.  That particular strain of bacteria no longer seems to exist, although a different form still affects people in a number of countries.

The medieval version was identified in the teeth of some of the London victims, dating from 1348-1350 CE.