The anti-vaccination movement has recently come into the spotlight after the resurgence of measles, a vaccine-preventable respiratory illness, has emerged across the United States in the past year. In this episode of Take as Directed, Steve Morrison speaks with Lena Sun, award-winning national health reporter for The Washington Post to discuss how the anti-vaxxer movement has evolved into what it is today—a small but vocal, social media-savvy, activist group of Americans. Over the course of her career, Lena has written widely on a number of issues related to public health and infectious disease, and her most recent work is on the topic of the anti-vaxxer movement in the U.S., its implications on public health, and state and federal responses to the anti-vaxxer movement.