The U.S. has lost measles elimination status. Here's what that means and who is most at risk.

Key Points:

• The United States has lost its measles elimination status, confirmed by the Pan American Health Organization (PAHO) after the country recorded over 5,400 measles cases in 2026, more than double the previous year's total.
• Measles elimination status requires no locally transmitted infections or outbreaks lasting 12 months or longer, a standard the U.S. failed to meet for the first time since 2000 due to ongoing outbreaks linked to declining vaccination rates.
• The largest outbreak has occurred in Pennsylvania, with over 1,500 cases and seven deaths, while measles cases have been reported in 45 states and Washington, D.C., leading to more than 590 hospitalizations and at least six deaths nationwide.
• Experts emphasize that regaining elimination status requires increasing vaccination coverage to 95% or higher, combating misinformation, and implementing policies that support vaccination, as most cases involve unvaccinated individuals.
• Measles poses significant risks, especially to vulnerable groups such as babies, pregnant women, and immunocompromised individuals, with complications including pneumonia, encephalitis, and death; the effective MMR vaccine remains the primary tool to prevent outbreaks.