In the last three weeks, 48 cases of measles have been identified, sending 13 patients to the hospital, according to the Texas Department of State Health Services.

A growing measles outbreak in west Texas has infected 48 people, according to official state data released Friday -- the latest sign that the once-vanquished childhood disease is making a comeback as vaccination rates decline.

Nine of those infected were hospitalized and more cases are likely, health authorities said. U.S. vaccination rates for measles are falling, according to the CDC.