Answer:
The bubonic plague, caused by the bacterium Yersinia pestis, was responsible for the Black Death that ravaged Europe in the 14th century. The disease was primarily carried by rodents, particularly black rats, which were infested with fleas that transmitted the bacterium to humans through their bites. Human contact with the rodents and their fleas was made more likely due to overcrowding and unsanitary living conditions in cities during this time. The disease was highly contagious and deadly, with mortality rates reaching up to 50-60% in some areas. In an effort to control the spread of the disease, measures such as quarantine and burning of infected materials were implemented. The Black Death had a significant impact on European society, leading to a decline in population, economic disruption, and changes in religious and cultural practices. It is estimated that the disease wiped out between 30-60% of the European population.