Lack of disease, misunderstandings about vaccine safety, and media coverage that makes highly unlikely side effects of vaccines sound not only plausible, but also likely, all play a role. For example, the hypotheses that vaccines cause autism and diabetes are causing alarm among some parents, even thought the best available scientific evidence does not support either of these hypotheses. Some parents are afraid that vaccines are not safe, which is not true. Before a vaccine can be used in the United States, it must be shown to be safe and effective. Because healthy children are typically the recipients of vaccines, safety requirements are especially stringent.
Information taken from the Internet can also contain false or misleading information.
Often, the scientific data does not support the conclusion, but these sites usually contain powerful anecdotes from parents who believe their children were harmed by a vaccine. That's very believable to another parent. In a nationwide phone survey on this topic, researches found a substantial minority of parents held important misconceptions about vaccination. NNii's mission is to provide the best possible science-based information to everyone who needs to know the facts about immunizations. As a disease-prevention program, NIP provides leadership for the planning, coordination, and conduct of immunization activities nationwide.