Black Plague

The Black Plague, more commonly called the Black Death, was a medieval plague pandemic caused by the bacterium *Yersinia pestis*.

The Black Plague, more commonly called the Black Death, was a medieval plague pandemic caused by the bacterium *Yersinia pestis*. It devastated Europe, Asia, and North Africa in the 14th century and is one of the deadliest disease events in recorded history. Plague still occurs today in small, treatable outbreaks in parts of the world.

Cause and origin

The Black Plague was caused by the bacterium *Yersinia pestis*, a finding confirmed by modern research. Historical and genetic evidence indicates that the medieval outbreak originated in Asia or central Eurasia before spreading westward into Europe.

Transmission

The disease was primarily spread by fleas that fed on infected rodents, particularly rats, and then bit humans. In cases of pneumonic plague, infection could also spread through close contact with respiratory droplets from infected individuals.

Symptoms and course

Typical symptoms included fever, vomiting, aches, and painful swelling of the lymph nodes, especially in the groin, neck, or armpits. In severe cases, patients could develop blackened skin lesions and die within days.

Impact and death toll

The Black Death devastated Eurasia in the 14th century and is commonly estimated to have killed about one-third of Europe’s population. Exact death totals are uncertain because medieval records are incomplete, but estimates range in the tens of millions.

Modern status

Plague still exists today in several parts of the world, including sporadic human cases in the Americas, Africa, and Asia. Modern antibiotics and public health measures usually make current cases treatable if diagnosed quickly.