Want to know how vaccines work? Check out this two minute video.

With the return of vaccine-preventable diseases and related conspiracy theories on the rise, PBS NOVA decided to investigate the state of immunization in America.

"Immunization plays a crucial role in our public health, yet there is a tremendous amount of apprehension and confusion around the topic," said Paula S. Apsell, senior executive producer for NOVA. So a new documentary — "Vaccines—Calling the Shots" — examines vaccine trends and the science behind them.

You can watch the whole thing here on Wednesday Sept. 10. For now, check out this clip that explains the concept of immunity in two minutes.

For more on why people should get vaccinated, see Sarah Kliff's post about vaccines and our cardstack on vaccines.

We have a request

Vox's journalism is free because we believe that everyone deserves to understand the world that they live in. That kind of knowledge helps create better citizens, neighbors, friends, parents, consumers and stewards of this planet. In short, understanding benefits everyone. You can join in on this mission by making a financial gift to Vox today. Reader support helps keep our work free, for everyone. Will you join us?

One-Time Monthly Annual

$95/year

$120/year

$250/year

$350/year

Other

$

Yes, I'll give $120/year

Yes, I'll give $120/year

We accept credit card, Apple Pay, and Google Pay. You can also contribute via