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Episode 2 Preview
Preview: Episode 2 | 30sVideo has Closed Captions
Data has been an essential public health tool since at least the seventeenth century.
Data has been an essential public health tool since at least the seventeenth century. Helping the world understand and mitigate the spread of disease, data has helped us make sense of the threats to our collective health.
![The Invisible Shield](https://image.pbs.org/contentchannels/nWRd1b3-white-logo-41-mPUkuHv.png?format=webp&resize=200x)
Episode 2 Preview
Preview: Episode 2 | 30sVideo has Closed Captions
Data has been an essential public health tool since at least the seventeenth century. Helping the world understand and mitigate the spread of disease, data has helped us make sense of the threats to our collective health.
How to Watch The Invisible Shield
The Invisible Shield is available to stream on pbs.org and the free PBS App, available on iPhone, Apple TV, Android TV, Android smartphones, Amazon Fire TV, Amazon Fire Tablet, Roku, Samsung Smart TV, and Vizio.
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The Invisible Shield
Explore the discussion guide for The Invisible Shield, a useful tool for extended learning related to the docuseries. The guide pulls out key themes from the show and presents questions that encourage critical thinking, powerful discussion, and expanded understanding regarding public health.Providing Support for PBS.org
Learn Moreabout PBS online sponsorshipSomething was killing people.
This new disease came along.
Battling a new pathogen is like a chess game.
You're using public health and social measures to shape the way the board will unfold.
Collecting data and analyzing it has probably saved many lives as the vaccines and the antibiotics.
The main problem facing our domestic public health infrastructure is that it's badly outdated.
When you ignore public health, a lot of people are going to die.
Cholera and the Modern Public Health System
Video has Closed Captions
How the 1854 cholera outbreak led to the birth of the modern public health system. (1m 12s)
Video has Closed Captions
Steven Johnson describes the origins of cholera and how interventions stopped the spread. (2m 57s)
Providing Support for PBS.org
Learn Moreabout PBS online sponsorship