First human case of screwworm parasite found in U.S. in person who traveled to El Salvador

The first human case of the flesh-eating parasite "New World screwworm" has been detected in the United States in a person who had recently traveled to El Salvador. NBC News medical contributor Dr. Kavita Patel talks about the risks to humans and the implication of the parasite's presence can mean for cattle and agriculture in the U.S.