Worst outbreak in history

Antonine Plague (165AD):

Death toll: 5 million

Cause: Unknown

Plague of Justinian (541-542):

Death toll: 25 million

Cause: Bubonic Plague

kill half of the europe population

The black death (1346-1353):

Death toll: 75-200 million

Cause: Bobonic Plague

(Live in rats)

Third cholera pandemic (1852-1860):

Death toll: 1 million

Cause: Cholera

Most deadly of the seven cholera pandemic

Flu Pandemic (1889-1890):

Death toll: 1 million

Cause: Influenz

Russian flu

Flu Pandemic (1918):

Death toll: 20-50 million

Cause: Influenza

It mostly attack healthy people, while leaving children and those with week immune system still alive.

Asian Flu (1956-1958):

Death toll: 2 million

Cause: Influenza

Flu Pandemic (1968):

Death toll: 1 million

Cause: Influenza

Kill 15% of Hong Kong

HIV/AIDS Pandemic (2005-2012):

Death toll: 36 million

Cause: HIV

To know more

https://therandomsci.com/2020/07/07/bubonic-plague/

https://therandomsci.com/2020/07/04/mother-of-all-pandemic-getting-stronger/