At least 58 cases have been confirmed. Health officials — who are scrambling to get a handle on the vaccine-preventable outbreak — suspect 200 to 300 people may be infected.

The measles outbreak first reported in Gaines County, Texas, has doubled to 48 cases since a count released earlier this week, the Texas Department of State Health Services said Friday. The first two cases were identified in late January and the numbers have been rising since.