The plague disease, caused by Yersinia pestis,…

The plague disease, caused by Yersinia pestis, is enzootic (commonly present) in populations of fleas carried by ground rodents, including marmots, in various areas including Central Asia, Kurdistan, Western Asia, Northern India and Uganda.

Nestorian graves dating to 1338–39 near Lake Issyk Kul in Kyrgyzstan have inscriptions referring to plague and are thought by many epidemiologists to mark the outbreak of the epidemic, from which it could easily have spread to China and India.

In October 2010, medical geneticists will suggest that all three of the great waves of the plague originated in China.