even "normal" vaccines are not without risk. for instance, in the early 2000s, the h1n1 flu vaccine ended up giving something like 1300 people in europe narcolepsy. and in the 70s, the swine flu vaccine gave a bunch of people all sorts of neurological disorders. vaccine immunity also tends to wane. for example, the chicken pox vaccine's immunity wanes after about 6 years, and by 20 years, it is basically gone. this makes most adults susceptible to shingles (the adult form of chicken pox, which is far more deadly). in some of the recent flu outbreaks, a majority of the flu cases were actually people who were vaccinated - including an aircraft carrier flu outbreak among 100% vaccinated population. turns out that polio wasn't cured by vaccines either. it was partially cured by "rebranding" it - changing the definition of polio from paralysis that lasts a few days to paralysis that lasts over a month. they also changed how polio was treated, thanks to a nurse kenny. the prevailing wisdom was to not move the constricted limbs, while she found out that through targeted therapy, moving the limbs actually cured polio. in fact, the entire physical therapy discipline is based on her work. there is almost certainly a connection between vaccines and autism, since delaying the vaccination schedule can directly affect the rates of autism (the most compelling piece i've read is that, like vaccine induced narcolepsy, autism is caused by multiple factors, but is triggered by a high fever during a particularly delicate developmental stage - vaccines just provide the fever, the vaccine schedule ensures it happens at the worst possible time). sure, vaccines work, but they don't work as well as advertised, and they are not without risk.
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