CDC

The vaccination rate for measles, mumps, and rubella (MMR) in Colorado is now 88%, sixth lowest among states that provided data. The state health department reported just under 88% MMR rates during the 2025-26 school year Last year, Colorado saw its highest number of measles cases since 1995.

The Trump administration changed a schedule that included things like the seasonal flu shot. The state will follow the American Academy of Pediatrics instead.

More than a dozen Democrat-led states found a coalition to share public health data, best practices, and more.