Health experts are warning travelers about measles as cases rise across North America.

Officials say someone with measles was at Philadelphia International Airport on Sunday, and last month there was an exposure at Newark Liberty International Airport.

The CDC reports more than 1,600 confirmed measles cases in the U.S. this year, including 11 in New Jersey.

Dr. Kisha Davis with the American Academy of Family Physicians said, "It's very concerning that we are seeing this illness to be on the rise, especially when we know that there are very simple steps that can be done to prevent it."

She says getting vaccinated against measles is the best and most effective way to stay protected.