Since the rapidly spreading novel coronavirus was first identified last year in China in Wuhan — a city of 11 million residents that is larger than any city in the United States — it has infected nearly 10,000 people on four continents, including six in the United States. As of the end of January, over 200 people around the world had died of the virus.

The U.S. Department of State issued on Jan. 30 the highest level travel advisory, warning Americans to not travel to any part of China, citing the World Health Organization’s determination that the outbreak constitutes a Public Health Emergency of International Concern.

As of Jan. 31, numerous vaccines, treatments, and diagnostic methods for coronavirus were in development, but developing an effective vaccine or treatment will likely take at least several more months.

Chinese authorities have accepted aid from the WHO in responding to the crisis. Authorities have enforced a quarantine of 50 million people living near the epicenter of the virus — the largest known quarantine in human history.

While the coronavirus outbreak is without a doubt one of the most serious international public health emergencies in recent memory, it is unlikely to come close to the devastation wrought by some of history’s worst outbreaks.

From the time of the pharaohs to the present day, epidemics of diseases like the bubonic plague, cholera, influenza, and smallpox have had a cataclysmic impact on civilizations. These scourges changed history, accelerated the decline of empires, decimated armies, and molded cultures.

To provide some historical context, 24/7 Wall St. has compiled a list of the worst outbreaks of all time.

Click here to see the 20 worst outbreaks of all time