According to an update by the Texas Department of State Health Services (DSHS), all 24 cases identified in the two-week-old outbreak are in unvaccinated people. Nine of the patients (37.5 percent) required hospitalization.

Measles — also called rubeola — is highly contagious and can be serious and even fatal for small children. While death rates have been falling worldwide as more children receive the measles vaccine, the disease still kills more than 200,000 people a year, mostly children, according to Mayo Clinic.org.