One of the largest measles outbreaks in decades is spreading along the Arizona-Utah border, with health officials confirming dozens of cases. Southwest Utah has reported 27 cases, nearly all among unvaccinated school-aged children.
Across the border, Mohave County, Arizona, has confirmed 42 cases, including one child who required hospitalization. The Arizona Department of Health Services called it the highest number of cases seen since the 1990s.
Vaccination Rates Behind the Surge
Experts point to low vaccination rates as the driving force behind the outbreak. In Washington County, Utah, only about 79% of kindergartners are protected against measles, far below the 95% threshold required for herd immunity.
At one school in Mohave County, just 7.7% of kindergartners were vaccinated last school year, according to NBC News.
David Heaton, spokesperson for the Southwest Utah Public Health Department, said:
“We are just at that low rate of (vaccine) uptake that does leave us open for this kind of an outbreak.”
Measles Risks and Symptoms
Measles is among the world’s most contagious viruses. Symptoms include fever, cough, runny nose, and a rash. The Mayo Clinic warns that it can lead to severe complications such as pneumonia, brain swelling, and even death.
Cases Rising Nationwide
The U.S. Centers for Disease Control and Prevention (CDC) has recorded 1,514 measles cases across 40 outbreaks in 2025 — the highest in more than 30 years. By comparison, only 16 outbreaks were reported in all of 2024.
Dr. Bob England, a former Arizona public health official, emphasized the predictability of this surge:
“This is exactly what you expect to see when you have a highly infectious vaccine-preventable disease drop into a community with low vaccination rates, almost inevitable.”
Federal Officials Urge Vaccination
Federal health leaders are now urging families to take action. Jim O’Neil, acting CDC director, said:
“I encourage parents to vaccinate their children. Vaccines not only protect individual children from measles but also contribute to community immunity.”
