Disease | Death toll | Transmission | R₀ | Case fatality ratio | Hospitalized cases sent to ICU |
Asymptomatic transmission |
Year vaccine available |
Pertussis | 160 000 in 2014²⁰ | Droplet | 9.9-11.5 | 4% | 1930s | ||
Diphtheria | 15 520 in 1921²¹ | Droplet | 6-7 | 5-10% | 1923 | ||
Measles | 140 000 in 2018²² | Airborne | 12-18 | 0.1-0.2% | 1963 | ||
Smallpox | 300-500 million in the 20th century²³ |
Droplet | 5-7 | 30% (variola major) | 1797 | ||
Rubella | Droplet | 5-7 | 3-6% (developing world) | 1970 | |||
Mumps | Droplet | 4-7 | 0.01% | 1967 | |||
SARS | 774¹⁹ | Droplet | 2-5¹ | 9.6%¹ | No | n/a | |
MERS | 858¹⁸ | Droplet | <1¹ | 34%¹ | No | n/a | |
2009 Swine flu (H1N1) |
284 000¹⁷ | Airborne | 1.64-1.88⁷ | 0.026%⁸ | Yes | 2009 | |
Seasonal flu | 400 000¹⁶ | Airborne | 1-2 | < 0.1% | 5-10%⁵ | Yes | seasonal |
1968-69 Hong Kong flu (H3N2) |
1-4 million¹⁶ | Airborne | 1.21-3.58¹¹ | <0.5%¹² | Yes | 1968 | |
1957-58 Asian flu (H2N2) |
1.5-4 million¹⁶ | Airborne | 0.5%²⁴ | Yes | 1957 | ||
1918 Spanish flu (H1N1) |
17.4-100 million¹⁶ | Airborne | 2-4¹³ | >2.5%¹⁴ | Yes | n/a | |
Coronavirus COVID-19 (SARS-CoV-2) |
TBD | Droplet⁹ | 1.4-2.5² 2.47-2.86⁶ |
0.5-1.6%⁴ | 22%¹⁵ 23%³ |
Suspected¹⁰ | n/a |