Bucks County's school vaccination rates are sliding as Pennsylvania's measles outbreak grows deadlier and wider.

A 40-year-old Jefferson County woman died Saturday, Sept. 12, from complications associated with measles, Jefferson County Coroner Greg Furlong announced Sunday, Sept. 13. She is the third person in the state whose death has been linked to measles this year, and the first outside Lancaster County, the Bucks County Courier Times reported.

Bucks County has reported zero confirmed measles cases as of the state's Sept. 11 update. But MMR immunization among Bucks County students averages 95.6%, down from 97.6% in the 2019-2020 school year, according to state data we reported on earlier this year. At least 12 Bucks County schools recorded kindergarten MMR rates below 90% in 2024.

Statewide, kindergarten vaccination stands at 93%, below the 95% threshold considered necessary for community immunity, Health Secretary Dr. Debra L. Bogen said Sept. 11.

The third death

Furlong said the woman was unvaccinated and developed symptoms after known exposure to people with confirmed and unconfirmed measles cases. Her death certificate lists respiratory failure caused by suspected measles, chronic obstructive pulmonary disease and asthma, Medical Daily reported.

Family members told the coroner she declined testing for measles before she died. Because no positive lab test exists, the case does not currently meet the state's formal definition of a measles-associated death.

The Pennsylvania Department of Health said Monday, Sept. 14, that it is conducting its own review of the Jefferson County case and has not issued a determination, according to 6ABC.

"This is a heartbreaking loss for the family and an unfortunate reminder that measles can be a serious and potentially life-threatening disease," Furlong said Sunday, Sept. 13.

Pennsylvania's two previous measles deaths both occurred in August and involved Lancaster County infants too young for the standard MMR vaccine, which is first administered at 12 months.

Statewide numbers

The state health department reported Friday, Sept. 11, that 676 cases have been confirmed in 37 counties this year, with 124 hospitalizations. Pennsylvania recorded 16 cases in all of 2025.

Lancaster County leads with 295 cases. Jefferson County, where the third death occurred, had 26. Neighboring Montgomery County has three confirmed cases.

Only four confirmed cases statewide involved fully vaccinated people, three adults and one child. None were hospitalized.

Pennsylvania and South Carolina lead the nation in 2026 measles cases, with 676 and 671 respectively, according to the Centers for Disease Control and Prevention (CDC).

What families can do

State health workers have held more than 120 pop-up MMR vaccination clinics since the outbreak began in late April, administering nearly 4,300 doses. Clinics have been set up at churches, fire halls, community centers and private homes, the Pennsylvania Capital-Star reported. Providers statewide gave more than 46,000 MMR doses in August, nearly double the typical monthly volume.

Under state health department guidance, unvaccinated students and staff may need to stay home for up to 21 days each time they are exposed to measles. Families can check their school's vaccination rate through a state dashboard launched in August using 2025-26 data.

The state measles hotline is 877-PA-HEALTH (877-724-3258), and county-level case counts are available at pa.gov/measles.