For World Immunization Week, we asked Heidi Larson, Ph.D., to share her thoughts on why there has been an uptick in people forgoing vaccines—and why they’re crucial to eliminating some of the world’s most pervasive diseases.

The documentary, airing on CNN and presented by Johnson & Johnson, looks at how our modern lifestyle may be responsible for perpetuating these lethal viruses—and how everyday citizens can fight back.