From the Black Death to modern-day outbreaks, how pandemics have shaped human civilization.

A pandemic is an epidemic of an infectious disease that has spread across a large region, for instance multiple continents or worldwide, affecting a substantial number of people. Widespread endemic diseases with a stable number of infected people such as recurrences of seasonal influenza are generally excluded as they are not novel. Throughout human history, there have been a number of pandemics of diseases such as smallpox and tuberculosis. The most fatal pandemic in recorded history was the Black Death (also known as The Plague), which killed an estimated 75–200 million people in the 14th century.