Investigating link between Zika and birth defects

Concerns continue to mount in the U.S. and abroad over the threat posed by the Zika virus. CBS News chief medical correspondent Dr. Jon LaPook recently returned from Brazil, the epicenter of the outbreak, where he spoke with the doctor who found the link between Zika and birth defects. CBS News contributor Dr. Holly Phillips joins “CBS This Morning” to discuss the virus in addition to a new study that finds why Americans' life expectancy is lower than other developed countries.