As the measles outbreak in West Texas continues to grow, North Texas doctors say they’re fielding a growing number of questions from concerned parents. Dr. Christopher Dreiling, a pediatrician at Pediatric Associates of Dallas, said his office has had “dozens and dozens” of measles inquiries.

Texas health officials say the number of people with measles has increased to 146 in rural West Texas outbreak that led this week to the death of a school-aged child who was not vaccinated

Measles is one of the most contagious viruses known to humans, experts say. Measles has been spreading across the U.S. for the last several weeks, sickening people in at least nine states amid a growing outbreak in western Texas.