It started with a single cough — now, officials fear a wider outbreak.

Health authorities in Utah have confirmed a new measles case as the illness spreads across the Utah–Arizona border, leaving more than 150 people infected. What’s more alarming, one patient in Salt Lake County is refusing to cooperate with investigators, blocking efforts to trace potential exposures.

“This person declined testing and won’t share where they’ve been,” said Dorothy Adams, executive director of the Salt Lake County Health Department. “But based on symptoms, this is very likely measles.” Without full cooperation, experts warn, contact tracing becomes nearly impossible — and the virus can move silently through schools, workplaces, and families.

Currently, vaccination rates in parts of Utah remain far below the 95% threshold needed for community protection. “One unvaccinated person can change everything,” a health spokesperson warned. Symptoms often begin like a common cold — fever, cough, runny nose — before a rash spreads and complications arise.

Officials are now urging every resident to check their MMR vaccine status. A single decision, they say, could save hundreds from illness. Because once measles starts spreading — stopping it becomes a race against time.