hm, i think the most is influenza virus. let looks at the time after world war. many are die because of flu, didn’t they?

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Best NOT be too light hearted about this subject.

Better to be afraid.

Be very afraid !

Robert K.

I think it would be hard to know precisely, especially if you mean over the centuries and not just in recent history. Certainly there have been major flu pandemics, but under normal circumstances, influenza kills mostly the very young or the very old. But maybe over centuries influenza would be the "winner." Plague killed millions and was indiscriminant, but was very episodic. Malaria kills thousands annually, and is likewise indiscriminant, but usually tends toward morbidity rather than mortality. Smallpox, Yellow Fever and Typhoid used to kill large numbers of people before vaccinations were possible. I wouldn’t rule out Cholera or Dysentery, either.

I have been scanning through my microbiology book(Brock, 11th edition) and was unable to find a statistic for what you need. However, if i were to make an educated guess, i would say influenza. The black death would be second, since it did kill many many people, but only acted over a few years.
I have been able to find a stat that shows the deaths by infectious diseases in the year 2002 – which, i think, can be used as an example for current times. The top five are:
1. Acute respiratory infections – 3963000 deaths
2. AIDS – 2777000 deaths
3. Diarrheal deseases – 1798000 deaths
4. Tuberculosis – 1566000 deaths
5. Malaria – 1272000 deaths
– from the World Health Organization, Geneva, Switzerland.

By the way, what do you think about those people saying that the black death was not plague?