With measles cases now confirmed in Oklahoma, health officials are urging the public to take precautions against one of the most contagious diseases in the world. Here's what you need to know about the disease.

Amid the outbreak of measles in West Texas, there's a question of how contagious the disease is—and whether it will spread in the Dallas-Fort Worth area.

Measles is caused by a highly contagious virus that's airborne and spreads easily when an infected person breathes, sneezes or coughs. It is preventable through vaccines, and has been considered eliminated from the U.S. since 2000.