GRAND JUNCTION, Colo. The U.S. is seeing the highest number of measles cases since it was eliminated from the country back in 2000.
Since the start of 2014, there have been 288 cases of measles reported to the Centers for Disease Control and Prevention.
Low vaccination rates contribute to the spread, which doctors say is harmful for babies especially because they can't be immunized until they're one year old.
"If you send your child to a daycare unimmunized, you're risking all the other children in that daycare who are too young to get that immunization and that's a burden you have to realize when you don't immunize yourself or your children," said Dr. Barb Zind, a Grand Junction pediatrician.
High rates of travel to countries where measles hasn't been eliminated also brings the disease back to the U.S. when people aren't immunized.
Colorado has one of the lowest immunization rates in the country.