A fast-growing measles outbreak in West Texas has nearly doubled in just one week, now totaling 90 cases across seven counties and spreading to New Mexico. Earlier this week, the Texas Department of State Health Services confirmed 49 cases in five counties.

Confirmed measles cases in Texas have reached at least 90, making this the worst measles outbreak in 30 years. Experts warn the number of Texas cases is likely much higher.

There is a measles outbreak in the South Plains region of Texas, with 58 confirmed cases, primarily in Gaines County, which accounts for 45 cases.