Should children be vaccinated? What was once an uncontroversial ritual has evolved into the roiling debate examined by this PBS "Frontline" documentary. As scientists and the medical establishment pit themselves against a select group of celebrities, alternative health gurus, and activists, concerned parents are left to wander through the tangle of research and social media declarations─not all of which add light so much as heat to the discussion. 60 min. Widescreen (Enhanced); Soundtrack: English Dolby Digital stereo; Subtitles: English (SDH).