DEADLIEST DISEASES IN HISTORY: THE BLACK DEATH: BUBONIC PLAGUE

 DEADLIEST DISEASES IN HISTORY: THE BLACK DEATH: BUBONIC PLAGUE

The Black Death ravaged most of Europe and the Mediterranean from 1346 until 1353. Over 50 million people died, more than 60% of Europe's entire population at the time.

Many historians believe it started in the Steppes of Central Asia, a vast grassland the area that even today still supports one of the world's most significant plague reservoirs - an area where rodents live in great numbers and density (also called a plague focus).

Plague is mainly spread through the bite of a flea infected with the plague-causing bacterium, Yersinia pestis. Fleas typically live on small animals such as rats, gerbils, marmots, squirrels, and periodically, explosive outbreaks of plagues occur among these susceptible hosts. Vast numbers of animals succumb to infection and die. Hungry fleas turn to humans, and within three to five days of a bite, fever, headache, chills, and weakness develop. Lymph nodes closest to the bite site swell to form a painful bubo in the variant of the plague known as bubonic plague. Infection may spread throughout the bloodstream and affect respiration in the lungs. Without prompt antibiotic treatment, 80% of infected people die within five days.