Just watched a broadcast from my professional society of a panel discussion on the outbreak of pertussis (whooping cough) in California, 2010, and which eventually spread nationwide. You can watch here: ASM video
This outbreak caused the death of 9 infants, plus hundreds of people becoming ill. When people who can be vaccinated but who don't, it endangers everyone because the herd immunity is lowered over all. The real efficacy of immunization is to deprive potential pathogens of viable hosts in which to colonize and propagate. It also protects the members in our society who cannot be vaccinated, like infants, the elderlies, and people with immune disease disorders. The vaccine opposition is endangering more than just their own health, but the overall health of everyone else around them.
Nine infants died, because of a preventable disease which went unprevented due to pseudo-science and mumble-jumble popularism. It's mind-boggling. Autism spectrum disorders are devastating to the parents of these children and it poses significant challenge to our medical science in terms of coming up with an explanation. But in the absence of a clear explanation (possibly, multiple explanations), we shouldn't cling on to made-beliefs, like vaccines being the cause of Autism Spectrum Disorders.