Pennsylvania has passed 1,000 measles cases in 2026, with 1,004 cases now reported across 39 counties, according to the latest update from the Pennsylvania Department of Health (DOH). At least 198 people have been hospitalized, and five measles-linked deaths have been reported.
Two of those deaths came from unvaccinated adults: an 18-year-old and a 40-year-old. Two more deaths were among infants too young to have received the MMR vaccine. The fifth death was in an unvaccinated resident of Lancaster County, in southeastern Pennsylvania; the individual’s age is unclear.
The Case Count
Lancaster County is the epicenter of the state’s outbreak, with 391 cases confirmed so far. Fewer than 1% of Pennsylvania’s cases are among those fully vaccinated with the MMR vaccine, according to DOH.
The national picture is worse. Nationwide, measles cases have surpassed 3,800 in 2026, with cases in 45 states and Washington, D.C., per CDC data. That is the highest number of illnesses since 1991.
The CDC recommends two doses of MMR vaccine: first at ages 12 to 15 months, second between 4 and 6 years old. One dose is 93% effective; two doses are 97% effective. Infants aged 6 to 11 months in high-risk areas may receive an early third dose.
The Death Toll
The deaths have drawn attention beyond Pennsylvania. Following confirmation of the fifth death, the CDC told ABC News it was “deeply saddened to hear of another death” in the state.
The CDC statement also noted that under Secretary Robert F. Kennedy’s leadership, CDC has provided Epi-Aid support to Texas, South Carolina, Virginia, Kansas, New Mexico, and Wisconsin. The CDC has not received a formal Epi-Aid request from Pennsylvania.
An Epi-Aid is a rapid, short-term field investigation of an “urgent public health problem.”
Vaccination Coverage
CDC data shows 92.4% of kindergartners received the MMR vaccine during the 2025 to 2026 school year, down from 95.2% in 2019 to 2020.
More than 8,800 MMR doses have been administered by DOH staff, including about 3,500 in August and more than 2,500 in September.
The Federal Response
The CDC has moved fast to help other states, providing Epi-Aid support to Texas, South Carolina, Virginia, Kansas, New Mexico, and Wisconsin. The agency has not received a formal request from Pennsylvania yet.
The CDC’s offer to help stands. Whether Pennsylvania asks for it remains to be seen.
What Happens Next
The outbreak is still growing. The DOH updates regularly, and the count will likely rise further before it falls.
The MMR vaccine is available, and the science is settled. The outbreak is real.
Pennsylvania has crossed a threshold it has not crossed in decades. The question now is what happens next.
Key Facts Box
- Cases: 1,004 across 39 counties
- Deaths: 5, including two unvaccinated adults
- Lancaster County cases: 391
- National cases: 3,800+, 45 states + DC
- Last major outbreak: 1991
- Kindergartner coverage: 92.4%, down from 95.2%
- Doses given: 8,800+
- Epi-Aid request: None from Pennsylvania
| State | Cases |
|---|---|
| Pennsylvania | 1,004 |
| Nationwide | 3,800+ |
The numbers are stark. The disease is serious. The vaccine exists.
Pennsylvania has crossed a threshold it has not crossed in decades.
Source material: “Measles cases surpass 1,000 in Pennsylvania amid the state's largest outbreak in decades,” ABC13 Houston.
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