The nation's top infectious disease doctor doesn't scare easy. But Tom Frieden — the head of the Centers for Disease Control and Prevention — is deeply worried about the rise of Zika virus, which is spreading across the Americas and causing birth defects in babies. And he's shocked that Congress, which has refused to fund the White House's emergency Zika request, doesn't share his concern.

Dr. Frieden joined POLITICO's Dan Diamond to explain how he thinks about global disease threats (starts at the 2:00 mark), why Zika is posing an unprecedented threat (4:30) and why CDC desperately needs funding to fight the ongoing outbreak (8:50), what's behind the nation's opioid epidemic (17:20), and whether Americans' public health is really getting better (21:30) Plus: Don't miss the lightning round quiz at 24:50.

In a bonus, POLITICO's Nancy Cook — who's been tracking health care issues on the 2016 campaign trail — explains why Republican candidates for Congress are starting to talk about the opioid epidemic, and what we know about Hillary Clinton and Donald Trump's health plans (28:40).

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