A sign is posted outside of a Pennsylvania Department of Health measles vaccination clinic located in Lancaster County in Peach Bottom, Pa., Tuesday, Oct. 20, 2026.
Matt Rourke/AP
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Matt Rourke/AP
The United States is grappling with the worst resurgence of measles in decades, with cases particularly high in the state of Pennsylvania.
New data from the US Centers for Disease Control and Prevention shows there have been more than 4,580 cases of measles in the US since October 22, more than double the number for all of 2025.
The vaccination status of 96% of those who contracted measles in 2026 was “Unvaccinated or unknown,” according to CDC data.
A measles outbreak has grown in Pennsylvania as officials urge residents to get fully vaccinated against the disease.
At least 1,338 cases of measles have been confirmed this year in 44 counties across the state, according to the Pennsylvania Department of Health on Friday. As of October 21, there were 21 new cases of measles. More than 250 people were hospitalized and 5 people died, the department also said.
In Lancaster and Mifflin counties, two of the counties with the highest number of cases, local Amish communities, which have low vaccination rates, are hardest hit. Of the five people who died, three lived in Lancaster County.
On Thursday, Pennsylvania Secretary of Health Dr. Debra Bogen hosted a roundtable with Mifflin County health care providers to assess their needs in combating the disease.
“Our state’s metrics and data tell part of the story of Pennsylvania’s measles outbreak, but listening to people on the ground caring for people in impacted communities like Mifflin County is critical to refining our public health response,” Bogen said in a statement.
According to health authorities, one of the best ways to protect yourself against measles is vaccination. Two doses of the measles-mumps-rubella vaccine, known as MMR, are nearly 97% effective against measles, according to the CDC. One dose is approximately 93% effective.
In Pennsylvania, the Department of Health said health care providers have found more residents want to get vaccinated against measles. Statewide, more than 39,000 measles vaccinations were administered in the first three weeks of October, higher than the statewide average of 25,000 vaccinations administered in a month, the Department of Health said.
Earlier this month, New York State Governor Kathy Hochul declared a state of emergency following a surge in measles cases. There have been more than 160 confirmed cases of measles statewide, according to Oct. 20 data from the New York State Department of Health.
Utah has also seen a high number of measles cases. More than 700 people in Utah have been diagnosed with measles this year, according to Oct. 20 data from the Utah Department of Health and Human Services. No measles diagnosis has been made in the state for 3 weeks, according to the department.
In South Carolina, which was facing an outbreak earlier this year, there have been at least 997 cases of measles in 2026, according to the South Carolina Department of Public Health. The epidemic ended in April.
Gn Health
