Die Another Day: The Mortality Gambit

Anyone who has spent time interfacing with the anti-vaccine denizens of major social networks has likely come across an argument such as this: Usually this argument is accompanied by some version of this graph: It is a compelling image, and the subtext here is clear: mortality was going down before vaccines were introduced. That proves that these diseases aren’t that dangerous. Modern sanitation and nutrition saved people, not vaccines! But what’s missing here? First let’s explore a couple terms that will help clarify: morbidity and mortality. Mortality versus morbidity Mortality is dying from an illness or other event. This is different from morbidity, which is having a complication from an illness or event.  For example: If I fall down a flight of stairs and get a bruise, that’s morbidity. If I fall down the stairs and break both my legs, that’s still a morbidity. If I fall down the same stairs and die, that’s mortality. For any given illness we can evaluate the morbidity (complication) rate, as well as the mortality (death) rate, but they are not the same thing.  So why were mortality rates going down even before immunization was available? Certainly modern standards of cleanliness and industrialization of … Continue reading Die Another Day: The Mortality Gambit