The United States has passed 5,000 measles cases in a single year for the first time in 35 years, according to new figures from the Centers for Disease Control and Prevention. The agency reported 5,182 confirmed measles cases as of November 5, up 330 from the 4,852 reported a week earlier. The total is more than double the 2,289 cases recorded in all of 2025, and the highest annual count since 1991.
Pennsylvania is the hardest-hit state. Its Department of Health has reported 1,487 cases and six deaths this year. South Carolina follows with 670 cases, and Utah has recorded 536. The CDC counts four measles deaths nationally in 2026. That figure differs from state tallies because the agency now tracks deaths through the National Center for Health Statistics rather than state health department reports. The CDC said it is working with the Council of State and Territorial Epidemiologists to settle on a single definition of a measles death.
Most of the infections have struck people who were not protected. The CDC said 96 percent of this year’s measles cases were among people who were unvaccinated or whose vaccination status was unknown. Of the total, 4,993 were linked to outbreaks. Hospitalizations reached 562, or 11 percent of reported cases.
Measles cases concentrated in Pennsylvania
The Pennsylvania outbreak has driven much of the national rise, and the state now accounts for more measles cases than any other. Three people died of measles in a single week: an infant in Wisconsin, a resident of Pennsylvania, and a child in Lewis County, New York. The Wisconsin infant was the state’s first measles death in more than 35 years. Pennsylvania’s health department has recorded six deaths, while the CDC’s national tally lists four, a gap that comes from the two different counting methods.
The rise in measles cases has continued week after week through the autumn. The CDC publishes updated counts each Friday, and the national total has climbed by hundreds of cases at each update. Health departments in the hardest-hit states have run vaccination clinics and traced contacts of confirmed patients, but the virus has kept finding people without immunity.
The 2026 total has already passed the worst year since the disease was declared eliminated. The previous peak came in 2019, when an outbreak centered in New York reached almost 1,300 cases and spread to 30 other states. The current count is four times that total, with two months of the year still to run when the CDC published its latest update. Only five states have reported no infections in 2026: Arkansas, Hawaii, Mississippi, Nevada, and New Hampshire. The CDC publishes updated counts weekly, so the national total is expected to keep rising while outbreaks continue.
Measles cases and the vaccination gap
Kindergarten coverage for the measles, mumps and rubella vaccine stood at 92.4 percent in the 2025-2026 school year, below the 95 percent level needed to stop the virus from spreading in a community. National coverage is about 92 percent for the first dose and 85 percent for the second, also short of the 95 percent threshold needed to halt transmission. Coverage has slipped in several states, and exemptions have risen. Measles spreads through the air and can linger in a room for up to two hours after an infected person leaves, which is why gaps in coverage show up fast once the virus arrives.
The disease was declared eliminated in the United States in 2000, which meant the virus no longer spread without interruption inside the country. Imported measles cases still arrived from abroad, but they did not start lasting chains of transmission. That run is now under threat. The Pan American Health Organization is due to review the country’s status next week, and the sustained spread since early 2025 has left the outcome in doubt.
The CDC will publish its next weekly update on Friday. Health officials will watch whether the weekly increase stays above 300 cases, a pace that would push the yearly total higher still before December. For now, the 5,182 measles cases stand as the largest annual count in a generation, and the outbreaks behind them show no sign of stopping.