UNITED STATES / RankWire.AI / – The United States is facing its worst resurgence of measles in decades, with cases particularly high in Pennsylvania. New data from the Centers for Disease Control and Prevention show more than 4,580 measles cases reported nationwide in 2026 as of October 22. That is more than double the number recorded for the whole of 2025. The CDC listed the vaccination status of 96% of this year’s patients as unvaccinated or unknown.
Pennsylvania’s outbreak has continued to grow as officials urge residents to get fully vaccinated. At least 1,338 measles cases have been confirmed in 44 counties so far this year, the Pennsylvania Department of Health said on Friday, October 23. The state reported 21 new cases as of October 21. More than 250 people have been hospitalized, and five people have died. The state had reported 943 cases in 39 counties at the start of October.
Lancaster and Mifflin counties are among the hardest hit in Pennsylvania. Local Amish communities, which have low vaccination rates, are being affected the most. Three of the five people who died lived in Lancaster County. On Thursday, Pennsylvania Secretary of Health Dr. Debra Bogen held a roundtable with Mifflin County healthcare providers. The meeting assessed what local clinicians need to combat the disease. Mifflin County lies in central Pennsylvania.
State officials push measles vaccination
Bogen said state data tell only part of the story of the outbreak. Listening to people caring for patients in affected communities is essential to refining the public health response, according to Bogen. Health officials say vaccination is one of the best ways to prevent measles. Two doses of the measles, mumps and rubella vaccine, known as MMR, are nearly 97% effective, according to the CDC. One dose is about 93% effective.
Healthcare providers in Pennsylvania have seen more residents seeking measles vaccination. More than 39,000 measles vaccines were given across the state during the first three weeks of October, the health department said. That compares with an average of about 25,000 doses administered statewide in a typical month. The outbreak had reached 693 cases and four deaths by mid-September. The surge in vaccinations came as case counts kept rising.
Outbreaks reported in several other states
Other states are also dealing with the disease. Earlier this month, New York Gov. Kathy Hochul declared a disaster emergency after a rise in cases. New York has recorded more than 160 confirmed measles cases, according to October 20 data from the state health department. Utah has diagnosed more than 700 people with measles this year. The Utah Department of Health and Human Services said there had been no new diagnoses in three weeks.
South Carolina, which faced an outbreak earlier in the year, has recorded at least 997 measles cases in 2026, according to its Department of Public Health. That outbreak ended in April. The national total now far exceeds last year’s count, with most cases among people who were unvaccinated or whose status is unknown. Pennsylvania remains the most active hot spot, with new cases still being reported. Health officials continue to urge eligible residents to receive both MMR doses.