Special Report

Worst Outbreaks of All Time

Source: William Faden / Wikimedia Commons

5. Smallpox Outbreak Among Native Americans
> Death toll: 20 million (estimated)
> Disease/Cause: Smallpox
> Affected area: North America
> Duration: Early 17th century-

The start of the reduction in the native population in North America began with the arrival of European settlers in early 17th century. It is not known how many indigenous people were in the Americas at the time Europeans arrived in the Western Hemisphere, but there is no doubt that the diseases they brought with them led to a historic depopulation of the Native people.

Source: Hulton Archive / Getty Images

4. 1918 Spanish Flu
> Death toll: 20 million
> Disease/Cause: Influenza (H1N1)
> Affected area: Europe, United States
> Duration: 1918-1919

The Spanish flu was one of the most calamitous events in human history. It shaped public policy in stressing annual vaccination initiatives and associated measures to fight the spread of the disease. The result of the death of so many males from the flu and World War I provided an opportunity for women to take on leadership roles and eventually led to the passage of the 19th Amendment in the United States that gave women the right to vote.

Source: Steve Eason / Getty Images

3. The HIV/AIDS epidemic
> Death toll: 39 million
> Disease/Cause: HIV/AIDS
> Affected area: Worldwide
> Duration: 1960-

Because the HIV/AIDS epidemic in the West first affected the gay community, stigma and discrimination was attached to it. The virus attacks the immune system and weakens it so the body can no longer fight infections and diseases. After years of demanding better health care and research, scientific advances like the development of antiretroviral drugs allow those afflicted with the disease to live longer lives with HIV. HIV annual infections declined by 8% in the United States and by 18% globally from 2010 to 2015, however, the disease is still highly prevalent in Africa, with 70% of global HIV cases.

Source: Wellcome Images / Wilkimedia Commons

2. The Black Death
> Death toll: 50 million-200 million
> Disease/Cause: Bubonic plague
> Affected area: Europe
> Duration: 1346-1350

The Black Death was one of the most convulsive events in European history. It depleted the labor force and reduced the amount of land that could be cultivated. The few workers who survived saw a drastic increase in their wages. This also caused a greater fluidity in the economy and some historians believe it hastened the end of the feudal system. Another unfortunate consequence of the Black Plague was the surge in anti-Semitism, which intensified after the Black Plague as Jews were blamed for the pandemic.

Source: Josse Lieferinxe / Wikimedia Commons

1. The Plague of Justinian
> Death toll: 100 million
> Disease/Cause: Bubonic plague
> Affected area: China, northern Africa, Mediterranean countries
> Duration: A.D. 541-542

The Plague of Justinian practically destroyed the Byzantine Empire in the sixth century. The pandemic reduced the size of the Byzantine army and its capacity to oppose enemies. The decrease in the population not only hurt the military, but also the economic and administrative structures of the empire, which began to collapse.