As COVID-19 continues to spread, fears and extraordinary predictions have also gone viral. While facing a new infectious threat, the unknowns of how new traits of our societies worldwide or of this novel coronavirus impact its spread. Though no two pandemics are equivalent, I thought it best to face this new threat armed with knowledge from past infectious episodes. The best inoculation against a plague of panic is to use evidence gained through billions of deaths, thousands of years, and a few vital breakthroughs to prepare our knowledge of today’s biological crises, social prognosis, and choices.

Below, I address three key questions: First, what precedents do we have for infections with catastrophic potential across societies? Second, what are the greatest killers and how do pandemics compare? Lastly, what are our greatest accomplishments in fighting infectious diseases?

As foundation for understanding how threats like COVID-19 come about and how their hosts fight back, I recommend reading The Red Queen concerning the evolutionary impact and mechanisms of host-disease competition and listening to Sam Harris’ “The Plague Years” podcast with Matt McCarthy from August 2019, which predated COVID-19 but had a strangely prophetic discussion of in-hospital strategies to mitigate drug resistance and their direct relation to evolutionary competition.

• The Biggest Killers:

Infectious diseases plagued humanity throughout prehistory and history, with a dramatic decrease in the number of infectious disease deaths coming in the past 200 years. In 1900, the leading killers of people were (1) Influenza, (2) Tuberculosis, and (3) Intestinal diseases, whereas now we die from (1) Heart disease, (2) Cancer, and (3) Stroke, all chronic conditions. This graph shows not that humans have vanquished infectious disease as a threat, but that in the never-ending war of evolutionary one-upmanship, we have won battles consistently since 1920 forward. When paired with Jonathan Haidt’s Most Important Graph in the World, this vindicates humanity’s methods of scientific and economic progress toward human flourishing.

However, if the CDC had earlier data, it would show a huge range of diseases that dwarf wars and famines and dictators as causes of death in the premodern world. If we look to the history of plagues, we are really looking at the history of humanity’s greatest killers.

The sources on the history of pandemics are astonishingly sparse/non-comprehensive. I created the following graphs only by combining evidence and estimates from the WHO, CDC, Wikipedia, Our World in Data, VisualCapitalist, and others (lowest estimates shown where ranges were presented) for both major historic pandemics and for ongoing communicable disease threats. This is not a complete dataset, and I will continue to add to it, but it shows representative death counts from across major infectious disease episodes, as well as the death rate per year based on world population estimates. See the end of this post for the full underlying data. First, the top 12 “plagues” in history:

 

Note: blue=min, orange=max across the sources I examined. For ongoing diseases with year-by-year WHO evidence, like tuberculosis, measles, and cholera, I grouped mortality in 5-year spans (except AIDS, which does not have good estimates from the 1980s-90s, so I reported based on total estimated deaths).

Now, let’s look at the plagues that were lowest on my list (number 55-66). Again, my list was not comprehensive, but this should provide context for COVID-19:

As we can see, the 11,400 people who have died from COVID-19 recently passed Ebola to take the 61st (out of 66) place on our list of plagues. Note again that several ongoing diseases were recorded in 5-year increments, and COVID-19 still comes in under the death rates for cholera. Even more notably, it has 0.015% as many victims as the plague in the 14th Century,

• In Context of Current Infectious Diseases:

For recent/ongoing diseases, it is easier to compare year-by-year data. Adding UNAIDS to our sources, we found the following rates of death across some of the leading infectious causes of death. Again, this is not comprehensive, but helps put COVID-19 (the small red dot, so far in the first 3 months of 2020) in context:

Note: darker segments of lines are my own estimates; full data at bottom of the post. I did not include influenza due to the lack of good sources on a year-by-year basis, but a Lancet article found that 291,000-645,000 deaths from influenza in a year is predictable based on data from 1999-2015.

None of this is to say that COVID-19 is not a major threat to human health globally–it is, and precautions could save lives. However, it should show us that there are major threats to human health globally all the time, that we must continue to fight. These trendlines tend to be going the right direction, but our war for survival has many foes, and will have more emerge in the future, and we should expend our resources in fighting them rationally based on the benefits to human health, not panic or headlines.

• The Eradication List:

As we think about the way to address COVID-19, we should keep in mind that this fight against infectious disease builds upon work so amazing that most internet junkies approach new infectious diseases with fear of the unknown, rather than tired acceptance that most humans succumb to them. That is a recent innovation in the human experience, and the strategies used to fight other diseases can inform our work now to reduce human suffering.

While influenzas may be impossible to eradicate (in part due to an evolved strategy of constantly changing antigens), I wanted to direct everyone to an ever-growing monument to human achievement, the Eradication List. While humans have eradicated only a few infectious diseases, the amazing thing is that we can discuss which diseases may in fact disappear as threats through the work of scientists.

On that happy note, I leave you here. More History of Plagues to come, in Volume 2: Vectors, Vaccines, and Virulence!

Disease	Start Year	End Year	Death Toll (low)	Death Toll (high)	Deaths per 100,000 people per year (global)
Antonine Plague	165	180	5,000,000	5,000,000	164.5
Plague of Justinian	541	542	25,000,000	100,000,000	6,250.0
Japanese Smallpox Epidemic	735	737	1,000,000	1,000,000	158.7
Bubonic Plague	1347	1351	75,000,000	200,000,000	4,166.7
Smallpox (Central and South America)	1520	1591	56,000,000	56,000,000	172.8
Cocoliztli (Mexico)	1545	1545	12,000,000	15,000,000	2,666.7
Cocoliztli resurgence (Mexico)	1576	1576	2,000,000	2,000,000	444.4
17th Century Plagues	1600	1699	3,000,000	3,000,000	6.0
18th Century Plagues	1700	1799	600,000	600,000	1.0
New World Measles	1700	1799	2,000,000	2,000,000	3.3
Smallpox (North America)	1763	1782	400,000	500,000	2.6
Cholera Pandemic (India, 1817-60)	1817	1860	15,000,000	15,000,000	34.1
Cholera Pandemic (International, 1824-37)	1824	1837	305,000	305,000	2.2
Great Plains Smallpox	1837	1837	17,200	17,200	1.7
Cholera Pandemic (International, 1846-60)	1846	1860	1,488,000	1,488,000	8.3
Hawaiian Plagues	1848	1849	40,000	40,000	1.7
Yellow Fever	1850	1899	100,000	150,000	0.2
The Third Plague (Bubonic)	1855	1855	12,000,000	12,000,000	1,000.0
Cholera Pandemic (International, 1863-75)	1863	1875	170,000	170,000	1.1
Indian Smallpox	1868	1907	4,700,000	4,700,000	9.8
Franco-Prussian Smallpox	1870	1875	500,000	500,000	6.9
Cholera Pandemic (International, 1881-96)	1881	1896	846,000	846,000	4.4
Russian Flu	1889	1890	1,000,000	1,000,000	41.7
Cholera Pandemic (India and Russia)	1899	1923	1,300,000	1,300,000	3.3
Cholera Pandemic (Philippenes)	1902	1904	200,000	200,000	4.2
Spanish Flu	1918	1919	40,000,000	100,000,000	1,250.0
Cholera (International, 1950-54)	1950	1954	316,201	316,201	2.4
Cholera (International, 1955-59)	1955	1959	186,055	186,055	1.3
Asian Flu	1957	1958	1,100,000	1,100,000	19.1
Cholera (International, 1960-64)	1960	1964	110,449	110,449	0.7
Cholera (International, 1965-69)	1965	1969	22,244	22,244	0.1
Hong Kong Flu	1968	1970	1,000,000	1,000,000	9.4
Cholera (International, 1970-75)	1970	1974	62,053	62,053	0.3
Cholera (International, 1975-79)	1975	1979	20,038	20,038	0.1
Cholera (International, 1980-84)	1980	1984	12,714	12,714	0.1
AIDS	1981	2020	25,000,000	35,000,000	13.8
Measles (International, 1985)	1985	1989	4,800,000	4,800,000	19.7
Cholera (International, 1985-89)	1985	1989	15,655	15,655	0.1
Measles (International, 1990-94)	1990	1994	2,900,000	2,900,000	10.9
Cholera (International, 1990-94)	1990	1994	47,829	47,829	0.2
Malaria (International, 1990-94)	1990	1994	3,549,921	3,549,921	13.3
Measles (International, 1995-99)	1995	1999	2,400,000	2,400,000	8.4
Cholera (International, 1995-99)	1995	1999	37,887	37,887	0.1
Malaria (International, 1995-99)	1995	1999	3,987,145	3,987,145	13.9
Measles (International, 2000-04)	2000	2004	2,300,000	2,300,000	7.5
Malaria (International, 2000-04)	2000	2004	4,516,664	4,516,664	14.7
Tuberculosis (International, 2000-04)	2000	2004	7,890,000	8,890,000	25.7
Cholera (International, 2000-04)	2000	2004	16,969	16,969	0.1
SARS	2002	2003	770	770	0.0
Measles (International, 2005-09)	2005	2009	1,300,000	1,300,000	4.0
Malaria (International, 2005-09)	2005	2009	4,438,106	4,438,106	13.6
Tuberculosis (International, 2005-09)	2005	2009	7,210,000	8,010,000	22.0
Cholera (International, 2005-09)	2005	2009	22,694	22,694	0.1
Swine Flu	2009	2010	200,000	500,000	1.5
Measles (International, 2010-14)	2010	2014	700,000	700,000	2.0
Malaria (International, 2010-14)	2010	2014	3,674,781	3,674,781	10.6
Tuberculosis (International, 2010-14)	2010	2014	6,480,000	7,250,000	18.6
Cholera (International, 2010-14)	2010	2014	22,691	22,691	0.1
MERS	2012	2020	850	850	0.0
Ebola	2014	2016	11,300	11,300	0.1
Malaria (International, 2015-17)	2015	2017	1,907,872	1,907,872	8.6
Tuberculosis (International, 2015-18)	2015	2018	4,800,000	5,440,000	16.3
Cholera (International, 2015-16)	2015	2016	3,724	3,724	0.0
Measles (International, 2019)	2019	2019	140,000	140,000	1.8
COVID-19	2019	2020	11,400	11,400	0.1

 

Year	Malaria	Cholera	Measles	Tuberculosis	Meningitis	HIV/AIDS	COVID-19
1990	672,518	2,487	670,000		1,903	310,000
1991	692,990	19,302	550,000		1,777	360,000
1992	711,535	8,214	700,000		2,482	440,000
1993	729,735	6,761	540,000		1,986	540,000
1994	743,143	10,750	540,000		3,335	620,000
1995	761,617	5,045	400,000		4,787	720,000
1996	777,012	6,418	510,000		3,325	870,000
1997	797,091	6,371	420,000		5,254	1,060,000
1998	816,733	10,832	560,000		4,929	1,210,000
1999	834,692	9,221	550,000		2,705	1,390,000
2000	851,785	5,269	555,000	1,700,000	4,298	1,540,000
2001	885,057	2,897	550,000	1,680,000	6,398	1,680,000
2002	911,230	4,564	415,000	1,710,000	6,122	1,820,000
2003	934,048	1,894	490,000	1,670,000	7,441	1,965,000
2004	934,544	2,345	370,000	1,610,000	6,428	2,003,000
2005	927,109	2,272	375,000	1,590,000	6,671	2,000,000
2006	909,899	6,300	240,000	1,550,000	4,720	1,880,000
2007	895,528	4,033	170,000	1,520,000	7,028	1,740,000
2008	874,087	5,143	180,000	1,480,000	4,363	1,630,000
2009	831,483	4,946	190,000	1,450,000	3,187	1,530,000
2010	788,442	7,543	170,000	1,420,000	2,198	1,460,000
2011	755,544	7,781	200,000	1,400,000	3,726	1,400,000
2012	725,676	3,034	150,000	1,370,000	3,926	1,340,000
2013	710,114	2,102	160,000	1,350,000	3,453	1,290,000
2014	695,005	2,231	120,000	1,340,000	2,992	1,240,000
2015	662,164	1,304	150,000	1,310,000		1,190,000
2016	625,883	2,420	90,000	1,290,000		1,170,000
2017	619,825		100,000	1,270,000		1,150,000
2018				1,240,000
2019
2020							16,514