Synopsis of some of the major pandemics, in chronological order, compiled based on the severity of the disease in terms of death toll.

Date Pandemic name Death toll
430 BC The plague of Athens 25% of population
1347–1351 Black death 200M
1520-onward New world smallpox 56M
1885 Third plague 12M
1918–1919 Spanish flu 40–50M
1981–present AIDS 25–35M
2009–2010 Swine flu 200K
2019–present COVID-19 >0.5M

Source: Extracted from The National Center for Biotechnology Information (NCBI), United States National Library of Medicine (NLM). Visit the site for a complete and detailed version of the pandemics-timeline.