The U.S. Centers for Disease Control and Prevention is advising those planning to travel internationally to make sure they’re vaccinated against measles. The warning, issued last week, says cases of the highly contagious disease are on the rise around the world.

Travelers visiting some popular cruise destinations are at an increased risk of contracting a concerning illness that’s spreading in the Caribbean, Mexico, and other areas.

The Centers for Disease Control and Prevention (CDC) has issued a comprehensive travel warning urging all Americans to ensure they’re fully vaccinated against measles before traveling internationally,