U.S. Loses Measles Elimination Status Amid Record Case Counts
The United States has officially lost its measles elimination status, researchers with knowledge of the decision confirmed to CBS News partner KFF Health News on Saturday, November 14, 2026. The determination from the Pan American Health Organization arrives after the nation recorded more than 5,400 measles cases in 2026, more than double the previous year’s total. The Pan American Health Organization functions as a regional office for the World Health Organization, covering North and South America.
According to World Health Organization standards, a country is considered to have eliminated measles when there are no locally transmitted infections or outbreaks lasting 12 months or longer. The United States failed to meet this threshold for the first time since achieving elimination status in 2000. Centers for Disease Control and Prevention data indicates that approximately one-third of 2026 cases are linked to continuous transmission chains originating in 2025.
Surging Infections and Severe Health Impacts
Following a 30-year high of 2,242 cases in 2025, the Centers for Disease Control and Prevention tallied 5,412 measles cases by mid-November 2026. These infections have resulted in more than 590 hospitalizations and at least six measles-related deaths nationwide, with individual states reporting additional fatalities. Infections have been confirmed across 45 states and Washington, D.C.
Pennsylvania has experienced the largest state outbreak, recording more than 1,500 cases and seven associated deaths this year. New York and Wisconsin have each reported at least one death. CBS News medical correspondent Dr. Céline Gounder explained that a country loses elimination status when population immunity drops sufficiently to sustain disease spread. While high vaccination rates normally cause isolated cases or small outbreaks to dissipate quickly, immunity gaps permit ongoing transmission chains.
Dr. Omer Awan, an epidemiologist and senior public health contributor for Forbes, described the designation change as a severe setback for public health infrastructure. Awan emphasized that the MMR vaccine is 97% effective at preventing measles onset, noting that the tool exists to prevent the surge but is underutilized.
Pathways to Regaining Elimination Status
To restore its elimination status, the U.S. must halt local transmission and eliminate outbreaks lasting longer than 12 months. The Pan American Health Organization dictates that maintaining a vaccination rate of 95% or higher, combined with sensitive surveillance systems, laboratory capacity, and rapid response mechanisms, is essential. Verified trend data must be submitted to the organization to secure reinstatement.
Experts point to declining childhood vaccination rates across numerous communities as a primary driver of the resurgence. Gounder noted that state-level policy decisions significantly influence immunization rates, highlighting that nine states relaxed school vaccine opt-out rules in 2025, whereas states terminating nonmedical exemptions experienced kindergarten vaccination increases of two to four percentage points. With most state legislatures scheduled to reconvene in January, lawmakers hold direct authority over upcoming exemption regulations.