Measles cases more than tripled this year. Here's how to help protect your kids as school starts.

As kids head back to school, federal health officials are emphasizing the importance of getting routine vaccinations against diseases like measles.

Over 200 cases of measles have been reported this year in more than two dozen states and Washington, D.C., which is more than triple the number of cases reported last year. Most are in children under 5 five years old who were not vaccinated or have an unknown vaccination status.

Dr. Mandy Cohen, director for the Centers for Disease Control and Prevention, said we're seeing more measles cases because it's "very contagious."