Measles, a highly infectious and preventable disease considered eliminated in the U.S. a quarter century ago, is now spreading in at least two states. Here are some answers to common questions about the disease, from how it presents to the durability of vaccinations.

Six years ago, two communities in New York – one in Brooklyn and one in Rockland County – were facing the worst measles outbreaks the United States had seen in decades. It was the closest the nation has gotten to losing elimination status for the extremely contagious disease,

A resurgence of measles is sweeping through communities nationwide. Health officials warn that the highly contagious virus, which had been nearly eradicated in many regions, is making a dangerous comeback,

Amid a growing measles outbreak in Texas — which led to the first death from the illness in the U.S. since 2015 — a second, also unvaccinated person has died in New Mexico, which borders the state.

The CDC is urging travelers to ensure they are vaccinated against measles as the outbreak spreads ahead of the spring and summer travel season.