As more and more parents are choosing not to vaccinate their children or are vaccinating them later, diseases like measles are making a comeback. Are vaccines safe? How do vaccines work? Why do some people claim there is a link between vaccines and autism? This week we look at why are people afraid of something that has saved so many lives, and look at the history and science of vaccines.

Originally released by Knowledgemotion, 2015. Streaming video file encoded with permission for digital streaming by Infobase on February 21, 2020.