Why is Zika virus spreading so quickly?

Aired: 1/28/2016 | 0:06:04 | Clip
Weeks ago, hardly anyone in the U.S. knew what the Zika virus was. Now the mosquito-borne illness is raising serious fears, especially for pregnant women. Judy Woodruff talks to Dr. Anthony Fauci of the National Institutes of Health about the dangers of the infection and how to prevent it, in absence of a vaccine.