Throughout history, pandemics have ravaged the world, often changing the course of events and sometimes ending civilizations. It has been a couple of months since the COVID-19 pandemic has swept the world with major social, political and economic effects, but some of the long-term consequences are still unknown. Pandemics are nothing new and looking back on history may help us understand the current pandemic further. Here are four of some of the most devastating pandemics to the human population.

Plague of Justinian (541-542 CE):  The plague is named after Emperor Justinian, the ruler of the Byzantine Empire, who, infuriated that his projects were not getting done because of the thousands that were dying, raised the taxes. The Plague of Justinian was identified as the Bubonic Plague, also known as the Black Death that ravaged the world in the 14th century. The plague, spread by a bacillus called Yersinia pestis, started from fleas and spread throughout the Mediterranean on the numerous trade routes. The disease was devastating and ended up killing 30 to 50 million people across Afro-Eurasia. 

Bubonic Plague, or Black Death (1347 – 1351): The Bubonic plague was not fully eradicated and came back 800 years later. In fact, some of the deadliest pandemics have been caused by Yersinia pestis. This bacteria is found among rodents and is thought to have originated in Asia and spread to Europe on trading ships. At the time no one knew how the Black Death spread from person to person, how to prevent it or how to treat it. However, some forward-thinking officials in Venice knew it had to do with proximity, leading them to keep incoming sailors on their ships. They were isolated for 30 days on their ships, but the isolation period was later increased to 40 days, or a quarantino, the origin of the word quarantine. This measure helped, but the plague killed an estimated 50 million people, about one-third of the world’s population. 

Third Cholera Pandemic (1852-1860): The third outbreak of cholera in the 1800s was the deadliest of the seven cholera pandemics. The disease originated in India out of the Ganges Delta and was rampant in Asia, Europe, North America and Africa. Unlike the plague, cholera is still a problem in the world, infecting 1.3 to 4 million people each year, and is caused by a bacteria that typically lives in warm and slightly salty water. Because of this, cholera is currently most common in developing countries that lack water and sewage treatment infrastructure. 

The Spanish Flu (1918): The 1918 influenza pandemic had a first wave in the spring, where cases were mild and the reported deaths were minimal. However, the flu came back in the fall of that same year and was more contagious and deadly than before. The strain of influenza was first detected in Europe, America and parts of Asia before it spread to the rest of the world. It did not originate in Spain. Spain was neutral in World War I and their media was the only one to cover the pandemic because other countries did not want to decrease morale. 

Looking back at these past pandemics that reshaped societies can help us better understand the COVID-19 pandemic and help us prevent similar situations in the future. We can learn from these pandemics, but viruses should also learn that we have defeated them in the past and will continue to do so in the future.