Virus pandemics are scary things. "The 1918 pandemic, by most estimates, killed 50 million from a 2000 million global population." The 2009 pandemic could have been this bad, or even worse. Many were scared that it would be really virulent and maybe reach the type of levels of death in the population which the Black Death caused. "The Black Death is estimated to have killed 30% to 60% of Europe's population, reducing the world's population from an estimated 450 million to between 350 and 375 million in 1400." 
But there are even more virulent things than viruses or bacteria that kill. Some things that we have no large scale healthcare systems to deal with. We have no quarantine system that will function on them — and the fact that these things can be deadly is not even widely recognised, even though it is easy to prove that they are. So what are they? They are memes. Memes that kill.
What is a meme?
"A meme is a unit of cultural ideas, symbols or practices, which can be transmitted from one mind to another through writing, speech, gestures, rituals or other imitable phenomena."
Memes are more virulent than viruses or bacterial plagues, as two people can transmit the meme between them without even being in the same country. The telephone system, TV, radio and lately the internet are the transmission vector for the meme. One person can in fact "infect" millions of people with a particularly successful meme and nearly at no cost.
What are some deadly memes, then?
- Government regulated, or "social" health care is worse than market regulated health care US style. This meme seems to have infected a rather large part of the US population, and it makes it much more expensive to run the US health care system, which as a result kills people. How many it kills I don't have the numbers for, but when you compare the cost for healthcare in the EU compared to the US, the latter gets worse healthcare (life expectancy: US 78.2; EU 78.7), costing significantly more (US: 14.5% of GDP, EU: 9.5% of GDP). (5% of US GDP is about US$ 730 Bn.) These billions could instead be used to save lives every year. Many lives. Certainly more than what the 2009 virus pandemic killed in the US.
- Climate change is a hoax. This meme has taken root among a fairly substantial part of the population in the Western world. The result will be that many people will die due to effects of climate change in places like Bangladesh, with increased flooding, or East Africa due to droughts.
- MMR vaccination is dangerous. The MMR vaccine is an immunisation shot against measles, mumps and rubella. This was a meme that made people think that vaccinating their children was more dangerous than not, as those who got this meme thought that their children would develop autism if they took the vaccine.
So the question is: What is the next big meme that is going to kill on a massive scale? Something as big as Nazism, which killed several tens of millions of people in only six years.
- Lucas Gonzalez, My ideal panflu. Retrieved 6 August 2010. | https://www.appropedia.org/TheFWD_lucasgonzalez_My_ideal_panflu
- Wikipedia, Black death, | http://en.wikipedia.org/wiki/Black_Death
- Wikipedia, Meme, first paragraph. Retrieved 6 August 2010. | http://en.wikipedia.org/wiki/
- Wikipedia, List of countries by life expectancy. Retrieved 6 August 2010. | http://en.wikipedia.org/wiki/List_of_countries_by_life_expectancy
- The Economist, A survey of health-care finance, The health of nations. 15 Jul 2004. Retrieved 6 August 2010. | http://www.economist.com/node/2895909
- IPPC, Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, 2007, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson (eds), Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Retrieved 6 August 2010. | http://web.archive.org/web/20181110071159/http://www.ipcc.ch/publications_and_data/ar4/wg2/en/contents.html
- Wikipedia, MMR vaccine, Safety. | http://en.wikipedia.org/wiki/MMR_vaccine#Safety
- Wikipedia, Casualties and war crimes. Retrieved 6 August 2010. | http://en.wikipedia.org/wiki/World_War_II#Casualties_and_war_crimes