The Black Death
Has 75 Million Deaths or More
Cause, Brief history, and Summary
The cause of The Black Death is thought to have originated in Central Asia, where it was most likely came from oriental rat fleas living on the black rats that were on merchant ships that came to Europe. The plague reduced the world population from about 450 million down to 350–375 million in the 14th century. The world population as a whole didn't recover to pre-plague levels until the 17th century. The plague recurred occasionally in Europe until the 19th century. The plague created a series of religious, social, and economic upheavals, which had profound effects on the course of European history.
How it's Transmitted, Risk Groups, Infectious Period, and Status
The plague disease is caused by yersinia pestis, an enzootic, commonly present in populations of fleas carried by ground rodents in various areas including Central Asia, Kurdistan, Western Asia, Northern India and Uganda. It's transmitted through being around or interacting with anything that has yersinia pestis and what it has touched/interacted with. In Europe, it's infectious period was during the years 1346–1353, during that time 75 - 200 million people died. It's not as risky as it was back then, but it's not fully gone.
Black Plague in Fingers
A hand showing how acral gangrene of the fingers due to bubonic plague causes the skin and flesh to die and turn black.
Oriental Rat Flea
Infected with the yersinia pestis bacterium which appears as a dark mass in the gut. The foregut, proventriculus, of this flea is blocked by a Y. pestis biofilm; when the flea attempts to feed on an uninfected host Y. pestis is regurgitated into the wound, causing infection.
Black Plague in the Thigh
An inguinal bubo on the upper thigh of a person infected with bubonic plague. Swollen lymph glands, buboes, often occur in the neck, armpit and groin (inguinal) regions of plague victims.