UNITED STATES / RankWire.AI / – Measles cases in the United States have climbed to their highest level in decades, with Pennsylvania at the center of the resurgence. The Centers for Disease Control and Prevention counted more than 4,580 cases in 2026 as of October 22. That total is more than twice the number reported across all of 2025. According to CDC data, 96% of this year’s patients were unvaccinated or had an unknown vaccination status.
In Pennsylvania, the state Department of Health confirmed at least 1,338 cases in 44 counties as of Friday, October 23. Twenty-one new cases were reported as of October 21. More than 250 people have needed hospital care, and five have died, the department said. Officials are urging residents to get fully vaccinated as the outbreak spreads. Pennsylvania had counted 943 cases across 39 counties earlier in October.
Amish communities in Lancaster and Mifflin counties, where vaccination rates are low, have been hit hardest. Lancaster County accounts for three of the five deaths. Pennsylvania Secretary of Health Dr. Debra Bogen met Mifflin County healthcare providers at a roundtable on Thursday to assess their needs. Bogen said state data capture only part of the picture. Hearing from frontline caregivers is essential to refining the response, Bogen said.
Demand for MMR shots climbs
Vaccination remains one of the most effective protections against measles, health officials say. The CDC says two doses of the measles, mumps and rubella vaccine are nearly 97% effective, while one dose offers about 93% protection. Pennsylvania providers have reported growing interest in the shots. Residents received more than 39,000 measles vaccines in the first three weeks of October. The state typically averages about 25,000 doses a month.
Pennsylvania reported 693 cases and four deaths in mid-September. The count has nearly doubled in the five weeks since then. The state confirmed its fifth measles-associated death in early October. The health department’s October 21 update said that only four cases, under 1%, had occurred in vaccinated people. The vast majority of infections have been among residents who were unvaccinated or whose status was unknown.
New York, Utah and South Carolina cases
The virus has also spread elsewhere. New York Gov. Kathy Hochul declared a disaster emergency earlier this month as cases rose. New York’s health department reported more than 160 confirmed cases as of October 20. In Utah, more than 700 people have been diagnosed with measles this year, according to its Department of Health and Human Services. Utah has not recorded a new diagnosis in three weeks.
South Carolina, which battled an outbreak earlier in the year, has logged at least 997 cases in 2026, its Department of Public Health said. That outbreak was declared over in April. Together, the state outbreaks have pushed the national count well beyond 2025’s total. Pennsylvania remains the most active hot spot, with new cases still being confirmed. Health officials continue to urge eligible residents to get both MMR doses.