I can't say my research has shown that on smallpox, but other diseases like the bubonic plague, German measles, influenza, and chickenpox for example are a handful of ailments vaccines weren't made to prevent, but rather treat. Hell, when the chickenpox vaccine was created, it was only meant to be used as a treatment; administration of that particular vaccine was most effective if taken within three days of being infected with chickenpox... it doesn't sound like a whole lot, but it gets darker when I told this finding to my own mother only to learn that when they were 17 they nearly died from chickenpox that they caught from their little sisters who got it at school. The doctors didn't understand what was going on because my mother had ALL their immunizations up to date, yet here they were sick as a dog. I've never caught chickenpox myself, and frankly, at my age death from it is almost a certainty. So outside of paranoia or my preservation of life instincts (two things humans are normally motivated by psychologically), my immunization is my last line of defense. Unfortunately, stories like that don't instill me with even the slightest bit of confidence that my immunization will actually work when I'll need it most.
Maybe it was the vaccines themselves, or maybe it was because the people being given them were all told this new serum would cure them; causing some sort of placebo effect. There were no control groups, and everyone was given the exact same thing at the same time, so there's no way of knowing which ingredient really did the trick, or if any of their ingredients worked. Frankly I don't even understand the relevance of 'chick embryo fibroblasts' or 'monkey kidney cells', or how having them injected into someone could help. Or why cell culture media (essentially steroids. But, growth hormones to be more succinct) are approved in vaccines given to newborns. Yes, most of these chemicals are seen in a large quantity of on the market too. But....
1. You're not injecting your food directly into your veins, there's a whole digestion process that often filters out indigestible substances.
2. The fact that there is such nonchalance to these things being in food or medicine gives me concern.