In a word: No. There is no evidence which shows any kind of connection between vaccinations and an increase in rates of autism among children. Many people who are suspicious of vaccines claimed a link between thimerosal (a mercury-based preservative) in vaccines and autism. However, there was no evidence linking exposure to thimerosal with autism; for example, there was no difference in rates of autism between children who got higher or lower doses of thimerosal. Additionally, in 2001 thimerosal was largely removed from childhood vaccines – even after the thimerosal was removed, rates of autism diagnosis actually increased. Had thimerosal in vaccines been a significant cause of autism, autism rates should have plummeted in the years since its removal, but no such drop has occurred. Not only that, but recent research indicates that the spectrum of autistic conditions are largely genetic in nature, with little to no environmental input. For more information on this topic, refer to the following links:
Food and Drug Administration – Thimerosal in Vaccines
Center for Disease Control – Vaccines and Thimerosal
Yes. Sometimes you’ll hear people complain that vaccines aren’t even needed because we no longer have outbreaks of measles, mumps, whooping cough (pertussis), polio, and other childhood diseases. But what those critics fail to realize is that the reason we don’t see widespread outbreaks of these diseases is precisely because of successful and widespread vaccination programs for children. In fact, if you look at parts of the developing world where vaccines are not common, these and other terrible diseases are seen to ravage populations just as it happened in our society over a century ago. We must not let down our guard – these diseases aren’t dead, they’re simply dormant. If enough people aren’t vaccinated within a certain region in the developed world, then these diseases re-emerge to cause localized outbreaks, sometimes with deadly consequences, as has been seen with localized outbreaks of Haemophilus Influenza B and Pertussis. A good example of what can happen when we let our guard down regarding vaccination rates is a measles outbreak that took place in California in 2008 – you can read more about it at the CDC’s website.
Herd immunity is basically the idea that if enough members of the population are vaccinated against a particular disease (roughly 80-95% for most diseases), then the disease will not be able to take hold and spread easily. Herd immunity is vitally important for protecting those members of the population who cannot be vaccinated themselves: newborn infants under 6 months of age, the elderly, those with pre-existing medical conditions, those with weakened immune systems, and those who have allergic reactions to vaccines. These people depend totally on herd immunity, so if there are enough people who decide NOT to vaccinate themselves or their children then they are actually putting other people’s lives at risk. More information on the science behind and importance of keeping up herd immunity can be found at the Science-Based Medicine blog.
Some parents are concerned that their young children may be getting too many vaccinations at once. As a result, some parents delay vaccinating their children as a middle ground; they think it's a safer and more conservative approach. However, as recent research has shown, there is no danger to having your kids vaccinated on a regular schedule as recommended by your doctor. The number of antigens in the current vaccine series (the parts of the vaccine that your body creates immunity to) is actually smaller than the number in many of the earlier schedules of vaccinations, while at the same time providing protection against more diseases. By sticking with the recommended vaccine schedule, parents ensure that their children are protected as early as possible. For more information on this particular question, see the CDC’s FAQ page on multiple vaccines & the immune system.
There are risks to vaccinating, but they are extremely rare. For example, some people cannot receive the influenza vaccination because they are allergic to eggs (and the flu vaccine is grown in egg yolk). The vast majority of people have no adverse reactions to vaccinations, and the benefits of vaccinating far outweigh the risks. If you don’t worry excessively about getting into a car accident when you drive, you shouldn’t worry about vaccinating; the odds of getting into a car wreck are far greater than having adverse reactions to a vaccine. If you want to learn more, see the CDC’s webpage on possible side-effects from vaccines.
There are many risks to not vaccinating yourself or your children. First, if you and your children are not vaccinated on a regular schedule, you put yourselves at risk for infection by a variety of serious & potentially fatal diseases (measles, pertussis, polio, etc). In addition, if enough people don’t vaccinate, then there could be a loss of herd immunity which is vitally important to protecting those who either have not or cannot be vaccinated (such as children too young to be vaccinated or the sick & elderly). In fact, there are a growing number of documented cases of mini-epidemics of diseases cropping up in communities where there are a large number of people who are not vaccinated. In some unfortunate cases, these mini-epidemics have led to fatalities. Vaccinating not only protects you and your children, but it also protects other people’s children.