Despite extensive scientific evidence, myths persist about the safety of vaccines, and their connection to autism. What impact do these misperceptions have on autism research? We’ll speak to Daniele Fallin, chair of the Department of Mental Health at the Johns Hopkins Bloomberg School of Public Health. And we’ll look into the risks of foregoing vaccines--the peril to individuals as well as the community at large. Dr. Kathy Neuzil, director of the University of Maryland School of Medicine’s Center for Vaccine Development, explains the concept of herd immunity.