I don't want to get into an argument over my decision not to vaccinate LO, but I want to say up front that I respect everyone's right to vaccinate or to refuse vaccination.
I could right pages and pages about why I chose not the vaccinate, but I'll try to simplify it here.
1.) I read about every vaccination and decided about them them individually. Ultimately, I decided that not one of them was worth getting based on either the seriousness of the disease and the rarity in my area. I.e., rotovirus is not serious -- it's annoying, but hardly every fatal; Polio can be very serious (I know a lot about this one in particular because I have family on both sides who worked with the original IPV vaccine) but it has been eradicated in North America.
2.) The ingredients are scary as A_K_and_K mentioned so I won't repeat it. I'll just add that I recently saw a study come out of UBC that found that aluminum in vaccines does a lot more harm than originally was conceived. I know that there are other toxins in food, the environment, etc., but I avoid them the best I can. DH and I are vegan and buy organic whenever we can; we stay away from second hand smoke and research the ingredients in whatever comes in contact with our bodies -- toothpaste, soap, plastics, etc. We're hardly every sick (DH hasn't been sick in 7 years) so maybe it helps? Choosing not to vaccinate is an extension of this mindset.
3.) Vaccines are not fully effective and the effectiveness doesn't last long in many cases. For instance, recent outbreaks of pertussis have occurred where over 80% of the people were fully up to date on vaccines.
4.) We don't know the long-term effects of vaccines; it's difficult to study possible complications, not to mention unethical (you can't every have a double-blind study examining the long-term effects of vaccinations -- nobody in their right mind would agree to that)! People didn't realize that they were getting tumors from polio vaccines contaminated with SV40 until it was too late.
I'd like to add that I kept my daughter inside for the first 6 weeks and I don't take her into crowded areas (and I won't for a while). I plan extended breastfeeding and to just do my best to build her immune system naturally. Natural exposure produces better and more long-lasting immunity anyway. However, I am always open to reexamining my views, and if there were an outbreak of something nasty in our area, my husband and I would reconsider our position.
Hopefully this stays respectful! I had NO idea it was such a touchy topic when I first started researching it.
Unfortunately, I have family members who no longer talk to us over our decision.