The ongoing measles outbreak along the Arizona-Utah border has surpassed 500 cases.
It began last August and, according to the states’ health departments, it reached 516 as of April 2—274 in Arizona and 242 in southwest Utah.
The outbreak is centered in the Short Creek community that includes Colorado City, Ariz., and Hildale, Utah. Mohave County has one of the lowest MMR vaccination rates in Arizona, and in 2024 it had dropped to 78.4% of the population.
More than 40 people have been hospitalized in both states because of measles.
Data from the Arizona Department of Health Services shows that infections have slowed in Mohave County since they peaked last December. In March, Arizona health officials confirmed 15 cases and in February there were 20.
In Arizona, 97% of measles infections were in unvaccinated people. And two-thirds of cases have affected people under 18 years of age.
Coconino County health officials have confirmed two measles cases since the beginning of 2026.
Meanwhile, measles cases in southern Utah and throughout that state have risen dramatically since the beginning of 2026. There have been more than 360 infections statewide since the beginning of the year with a majority in the southwest portion of the state.
