That reads like some serious straw clutching to justify your stance.. Take smallpox, for example. When the vaccine for that was created, it's estimated that nearly half a million people a year died of it in 18th century Europe. That's quite a lot when you consider that it's also estimated to be around 700 million people in the world in 1800. Which, if you extrapolate for the entire 18th century is approximately 40,000,000. Which means that even though the vaccine was derived from something milk maids were most likely to get - the cowpox virus - it was still common enough to affect people that had zero chance to encounter the milder variant and develop a natural immunity. Coincidentally, the wars in that period aren't that high. Technically, slavery killed more people than any of the wars in that period..