The number of measles cases linked to an outbreak in West Texas has grown to 58, according to the Texas Department of State Health Services.

The largest measles outbreak in decades has reached San Antonio and San Marcos. Officials say an individual who tested positive for the virus in West Texas traveled to two major universities and one of the nation's busiest tourist attractions — the San Antonio River Walk.

Texas reported 90 cases this week, while New Mexico reported nine. A majority of the cases have been in a Texas county where vaccination rates have lagged behind the rest of the state.