Pennsylvania has asked the Centers for Disease Control and Prevention for emergency epidemiological assistance as the state’s measles outbreak reached 731 confirmed cases across 38 counties. The request followed four deaths that state officials classify as measles-associated, according to Reuters’ September 17 report. The state’s definition covers deaths in which measles caused or contributed to the death, or could not be ruled out; it does not mean the virus was necessarily the sole cause.
The requested “Epi-Aid” would bring CDC Epidemic Intelligence Service officers and other specialists into the response. The CDC describes an Epi-Aid as rapid, short-term technical assistance—often one to three weeks and usually on site—to help public-health agencies investigate urgent problems. Such teams can support case tracking, data analysis, laboratory coordination and control recommendations, while the state retains authority over its response.
The request comes as the outbreak continues to expand. In a September 14 update, the Pennsylvania Department of Health reported 693 cases and 133 hospitalizations. That report said just four confirmed cases involved people documented as vaccinated. The later count represents 38 additional confirmed cases in several days.
State officials have also expanded vaccination access. By September 14, the department said nearly 4,300 measles-mumps-rubella vaccine doses had been administered at 130 pop-up clinics, while state health centers had delivered more than 6,300 MMR doses during 2026. Pennsylvania usually records about 25,000 MMR vaccinations a month, but more than 46,000 doses were given in August. The department says two MMR doses are about 97% effective at preventing measles.
The Pennsylvania surge is part of a broader national resurgence. The CDC’s current national tally lists 3,471 confirmed U.S. cases and 39 outbreaks in 2026, with 95% of cases linked to outbreaks. Federal and state death totals have not been identical; Reuters reported that Pennsylvania asked the CDC to recognize the state’s four measles-associated deaths in national reporting. That difference concerns surveillance classifications, not the state’s immediate guidance to residents.
What Pennsylvanians should do
The Health Department’s measles hub advises residents to check whether they have received two MMR doses and to contact a health-care provider or state health center if they are unsure. Measles symptoms generally appear seven to 21 days after exposure and can include fever, cough, runny nose, red eyes and a spreading rash. Because the virus can remain airborne for up to two hours, anyone who suspects measles should call ahead before visiting a clinic or emergency department so staff can limit exposure to others.
Residents can follow county-level case, hospitalization and vaccination data on the state dashboard or call the department at 877-724-3258. The practical message from the response is unchanged: confirm vaccination status promptly, watch for symptoms after a known exposure and alert providers before arriving for care.
