Shouldn't there be a _lot_ of very good data about this in the general case, not just for widely recognized anomalous events? I suspect adverse reactions are under-reported. A recent experience does nothing to dissuade me from that notion. (I know, confirmation bias). But the sheer number of vaccinations that take place would provide some very good data. Of course, that data would also probably show at least some occasional quality control problems with vaccines. No matter how much I may respect the science behind vaccination, I refuse to simply have faith that there are never any QC problems with the mass production of vaccines (or any product for that matter).
Our youngest developed a _very_ bad cough in the days/weeks after receiving the DTaP. We called the pediatrician who gave us the standard advice, to monitor the baby and bring her in if it worsened. We later did take the baby in for the cough. The doctor began dissuading us from the idea that it was Pertussis or related to the vaccination, before seeing the baby, and despite local news reports indicating a local increase in Pertussis cases[1]. The doctor had a look at the baby, and told us again it probably wasn't Pertussis, everything was normal (except the cough and low grade fever), ran a blood test for Influenza (tests confirmed that it wasn't Influenza), and told us to use a humidifier. I asked what the procedure (WRT both treatment and reporting) would be if it had been a possible or suspected vaccine adverse reaction. The doctor said they had _never_ had any reportable cases of vaccine adverse reaction and indicated a general lack of knowledge of adverse event reporting requirements. The clinic where this occurred was right across the street from the hospital that baby was born in, in the Medical Center in Houston, Texas, and is part of a large and well respected practice. Considering the number of patients that clinic has (it is a busy practice, with several clinics), even considering the low expected rate of serious adverse vaccination events, it is not possible that this clinic has never had a reportable event, and very unlikely that there were no serious adverse events. Baby might not have had Pertussis and baby is fine now. But, the experience turned my skepticism into a lack of confidence, at least with that particular clinic.
[1] http://www.chron.com/news/houston-texas/article/Whooping-cou...