The number of statewide measles cases confirmed in 2026 eclipsed 575 this week, though officials have yet to report a case in Northeast Pennsylvania as the case count elsewhere continues to climb.
The most recent figures, updated Friday by the state Department of Health, show 577 measles cases confirmed this year after Pennsylvania recorded just 16 cases of the highly contagious viral respiratory disease in 2025. Of those 577 total cases, 115, or about 20%, were new cases confirmed over the prior week.
Lancaster County remains the hardest hit with 246 measles cases, which represents almost 43% of the statewide total. It also accounts for the two “measles-associated deaths” the state Health Department announced late last month, the first deaths related to measles in Pennsylvania in 35 years. Officials at different levels of government who disagree over the role measles played in those deaths have publicly clashed in the wake of that announcement.
That dispute notwithstanding, none of the 577 people confirmed to have contracted measles was fully vaccinated against the disease, per the state.
The measles, mumps and rubella (MMR) vaccine remains the best way to protect against measles, local doctors told the newspaper in recent weeks. Gary Decker, M.D., director of infection control services for Commonwealth Health’s hospitals in Lackawanna and Luzerne counties, described it as “a time-honored vaccine with proven efficacy and a proven safety record.”
He recently attributed a yearslong national trend of declining childhood vaccination rates to several factors, including “pervasive” anti-vaccine narratives and misinformation contributing to vaccine hesitancy. The prevalence of anti-vaccine narratives on the internet is making that hesitancy more widespread, Decker said in an August interview.
State Department of Health staff had administered 6,025 doses of the MMR vaccine this year as of Friday.
Mifflin County accounts for the second most confirmed measles cases in the state with 57, followed by Chester County, which borders Lancaster County, with 56. Those three counties collectively account for about 62% of the year-to-date cases confirmed in Pennsylvania as of the state’s last update.
No cases have been confirmed in the seven-county region of Northeast Pennsylvania that includes Lackawanna, Luzerne, Monroe, Pike, Susquehanna, Wayne and Wyoming counties. Schuylkill County has also yet to record a measles case this year.