Vaccines are generally considered to be the most successful public health intervention ever devised. The successful use of vaccines in preventing disease means that most parents of young children in first world countries today have never seen a life-threatening case of diphtheria or polio.
Unfortunately, a small minority of people with a loud voice actively oppose immunization. They claim that vaccines do not work, despite the overwhelming evidence that they do. They often spread misinformation about vaccines, such as the notion that vaccines weaken the immune system, when in fact they work by strengthening the immune response against the target infection. They claim that vaccines cause autism, and that vaccines are responsible for a host of other illnesses – despite an overwhelming convergence of evidence to the contrary.
Their messages, which are often dramatic and misleading, receive wide publicity through print, radio, television, and the Internet.
Myths and misconceptions about vaccine safety are already contributing to a decrease in the number of people who are immunized against vaccine-preventable diseases such as measles, polio, and mumps. This has resulted in outbreaks of diseases that are seldom seen these days in developed countries. For example, the U.S. experienced 23 measles outbreaks in 2014, including one large outbreak of 383 cases, occurring primarily among unvaccinated Amish communities in Ohio.
Ultimately, anti-vaccine fear mongering can cause confusion for people who want to make responsible, informed decisions about immunization for their children, themselves, and the community. The continued success of immunization programs depends on a high level of public participation due to confidence in the safety of vaccines.
Take a look at this infographic, produced by Futurism, to better understand a few vaccine myths and misconceptions (click to see a larger, more legible version).