WORLD HISTORY

Detailed explanation-1: -Plague bacteria are most often transmitted by the bite of an infected flea. During plague epizootics, many rodents die, causing hungry fleas to seek other sources of blood. People and animals that visit places where rodents have recently died from plague are at risk of being infected from flea bites.

Detailed explanation-2: -Cholera, bubonic plague, smallpox, and influenza are some of the most brutal killers in human history. And outbreaks of these diseases across international borders, are properly defined as pandemic, especially smallpox, which throughout history, has killed between 300-500 million people in its 12, 000 year existence.

Detailed explanation-3: -1. Bubonic Plague. Bubonic Plague is a potentially fatal infectious disease caused by the bacterium, Yersinia pestis. Throughout centuries, the disease has erupted several times in different eras, claiming between ten and millions of lives worldwide.

Detailed explanation-4: -The Black Death (also known as the Pestilence, the Great Mortality or the Plague) was a bubonic plague pandemic occurring in Western Eurasia and North Africa from 1346 to 1353. It is the most fatal pandemic recorded in human history, causing the deaths of 75–200 million people, peaking in Europe from 1347 to 1351.