HIstory of pandemics

Death Toll: 5 million
Cause: Unknown
Also known as the Plague of Galen, the Antonine Plague was an ancient pandemic that affected Asia Minor, Egypt, Greece, and Italy and is thought to have been either Smallpox or Measles, though the true cause is still unknown.

Death Toll: 25 million
Cause: Bubonic Plague
Thought to have killed perhaps half the population of Europe, the Plague of Justinian was an outbreak of the bubonic plague that afflicted the Byzantine Empire and Mediterranean port cities, killing up to 25 million people in its year long reign of terror.

Death Toll: 75 – 200 million
Cause: Bubonic Plague
From 1346 to 1353 an outbreak of the Plague ravaged Europe, Africa, and Asia, with an estimated death toll between 75 and 200 million people. Thought to have originated in Asia, the Plague most likely jumped continents via the fleas living on the rats that so frequently lived aboard merchant ships.

Death Toll: 1 million
Cause: Cholera
Generally considered the most deadly of the seven cholera pandemics, the third major outbreak of Cholera in the 19th century lasted from 1852 to 1860. Like the first and second pandemics, the Third Cholera Pandemic originated in India, spreading from the Ganges River Delta before tearing through Asia, Europe, North America and Africa and ending the lives of over a million people.

Death Toll: 1 million
Cause: Influenza
Originally the “Asiatic Flu” or “Russian Flu” as it was called, this strain was thought to be an outbreak of the Influenza A virus subtype H2N2, though recent discoveries have instead found the cause to be the Influenza A virus subtype H3N8. The first cases were observed in May 1889 in three separate and distant locations, Bukhara in Central Asia (Turkestan), Athabasca in northwestern Canada, and Greenland

Death Toll: 800,000+
Cause: Cholera
Like its five previous incarnations, the Sixth Cholera Pandemic originated in India where it killed over 800,000, before spreading to the Middle East, North Africa, Eastern Europe and Russia. The Sixth Cholera Pandemic was also the source of the last American outbreak of Cholera (1910–1911).

Death Toll: 2 million
Cause: Influenza
Asian Flu was a pandemic outbreak of Influenza A of the H2N2 subtype, that originated in China in 1956 and lasted until 1958. In its two-year spree, Asian Flu traveled from the Chinese province of Guizhou to Singapore, Hong Kong, and the United States.

Death Toll: 36 million
Cause: HIV/AIDS
First identified in Democratic Republic of the Congo in 1976, HIV/AIDS has truly proven itself as a global pandemic, killing more than 36 million people since 1981. Currently there are between 31 and 35 million people living with HIV, the vast majority of those are in Sub-Saharan Africa, where 5% of the population is infected, roughly 21 million people.