This topic is much more complex than most people realize. From a public health perspective and from a statistical standpoint, it's a no-brainer to vaccinate all children against all major diseases. However, the view from an individual perspective is different. There are risks associated with each type of vaccination that are entirely unrelated to the autism study cited by so many. Here is just one example:
http://www.ncbi.nlm.nih.gov/pubmed/39253
I am totally in favor of pertussis vaccination, but it does double an individual child's risk of encephalitis. This doesn't matter unless it's ***your*** child who develops encephalitis. This is the perspective of the parent.
Individual reactions to vaccines vary. Health professionals need to take this into account. Until they do, parents will continue to try to protect their children from low-probability vaccination reactions at the expense of high-probability public health epidemics.