US Measles Cases Top 4,580 in Worst Decades Outbreak
- The United States is currently experiencing its worst resurgence of measles in decades, driven by climbing case numbers that have already surpassed 4,580 infections nationwide, according to data...
- According to data from the CDC, the vaccination status of 96% of individuals who contracted measles in 2026 was categorized as unvaccinated or unknown.
- Pennsylvania remains particularly hard-hit by the national resurgence.
The United States is currently experiencing its worst resurgence of measles in decades, driven by climbing case numbers that have already surpassed 4,580 infections nationwide, according to data from the U.S. Centers for Disease Control and Prevention. This total is more than double the number of infections confirmed across the entire country during 2025.
National Spread and Vaccination Rates
According to data from the CDC, the vaccination status of 96% of individuals who contracted measles in 2026 was categorized as unvaccinated or unknown. Kindergarten-level measles, mumps, and rubella (MMR) vaccination rates across the country have fallen away from the ideal 95% coverage threshold necessary to stop widespread outbreaks for several years. The CDC reported an MMR coverage rate of 92.4% during the 2025–26 school year, leaving hundreds of thousands of kindergarteners attending school while vulnerable to measles.
State Outbreaks Across Pennsylvania and Beyond
Pennsylvania remains particularly hard-hit by the national resurgence. The Pennsylvania Department of Health reported Friday that at least 1,338 cases of measles have been confirmed across 44 counties in the state this year, including 21 new cases logged as of October 21. More than 250 people have been hospitalized statewide, and 5 individuals have died. Lancaster and Mifflin counties have experienced the highest concentrations of cases, heavily impacting local Amish communities with low vaccination rates. Three of the five deaths occurred in Lancaster County.
Other states are also managing significant outbreaks. New York Kathy Hochul declared a disaster emergency earlier in October following a rise in infections, with the New York State Department of Health recording over 160 confirmed cases as of October 20. In Utah, more than 700 people have been diagnosed with measles this year according to October 20 data from the Utah Department of Health and Human Services, though the state has not recorded any new diagnoses in three weeks. Meanwhile, South Carolina recorded at least 997 cases during an outbreak that ended in April.
Public Health Responses and Official Statements
On Thursday, Pennsylvania Secretary of Health Dr. Debra Bogen held a roundtable with Mifflin County healthcare providers to evaluate local needs and coordinate the public health response. Our state metrics and data tell part of the story of the measles outbreak in Pennsylvania, but listening to the people on the ground caring for people in affected communities like Mifflin County is essential to refining our public health response,
Bogen said in a statement.
The measles outbreak is occurring because so many people went unvaccinated during the COVID pandemic,
Kennedy said. Kennedy referenced historical diary entries from Dr. Anthony Fauci, a longtime National Institutes of Health scientist, detailing early pandemic concerns that more than one million children worldwide had missed routine vaccinations due to shutdowns.
Immunization Efforts and Next Steps
Health officials maintain that vaccination is the most effective defense against the virus. Two doses of the MMR vaccine are nearly 97% effective against measles, while a single dose is about 93% effective, according to the CDC. Amid the current outbreak, Pennsylvania healthcare providers have observed an increase in residents seeking immunizations. The state health department reported that more than 39,000 measles vaccines were administered during the first three weeks of October, surpassing the typical monthly average of 25,000 doses. The U.S. and Mexico are scheduled to meet with the Pan American Health Organization next month to review regional measles elimination statuses.