HARRISBURG — Measles is spreading in Pennsylvania with case counts mushrooming since spring and not slowing down, all while schools across the commonwealth are on the precipice of opening doors to millions of students.
The Department of Health reported 296 cases so far this year were confirmed in 19 counties as of Friday, primarily in Lancaster County and overwhelmingly since May. It’s a small number when compared to Pennsylvania’s population of 13 million, and even its 1.7 million students who attend K-12 schools, and the current outbreak hardly approaches pandemic level.
But, it’s an extraordinary figure considering that between the year 2000 and 2025, there were just 112 cases combined in Pennsylvania, state Health data show.
In seven of those years, there were zero cases.
“I have not felt panic or concern. There is obviously going to be concern,” said Allison Palombo, a school nurse at Beaver Area School District in Beaver County, where there are no reported cases.
Palombo said she recommends to families that they fully immunize their children in accordance with the vaccine schedule recommended by the American Academy of Pediatrics. She also helps in finding places for immunizations, such as at local pharmacies, family practices and elsewhere.
There’s no specific medical treatment to cure measles; rather, medical experts recommend vaccination.
Below herd immunity
Herd immunity is achieved when 95% or greater of a population is vaccinated with the MMR vaccine for measles, mumps and rubella, according to the Centers for Disease Control and Prevention. Vaccine rates for kindergarteners nationally fell to 92.5% in 2024-25, down from 95.2% in 2019-20, according to CDC’s latest publicly available data.
Pennsylvania’s vaccine rate among kindergarten students in 2025-26 was 93.2%. The figure swelled among older age groups: 7th grade, 94.6%; 12th grade, 96.9%.
A vaccine database released this week by the administration of Gov. Josh Shapiro showed nearly 880 schools across the commonwealth fell below 95% among kindergarteners. The database is searchable by school, county and more, and includes rates beyond the MMR vaccine.
“I try to respect their boundaries and their rights,” Palombo said of vaccine opponents, “but at the same time I do want them to understand the safety aspect of it.”
CDC maintained this week that the vaccine is safe and effective, though President Donald Trump signed an executive order recommending the shot be administered in three separate doses rather than the single shot in which it’s commonly delivered.
“(Monday’s) executive order is not based on ‘gold-standard science.’ There is no new evidence to justify significant changes to childhood immunization guidance. Dozens of studies involving millions of people show there is no link between vaccines and autism, and yet federal leaders continue to promote this outdated, disproven idea to scare families,” Dr. Andrew Racine, president, American Academy of Pediatrics , said in a statement this week.
Required vaccine
Measles is also known as rubeola. The highly contagious disease is spread person to person through saliva, such as through a sneeze. It can also live 2 to 4 hours on certain surfaces, the Cleveland Clinic states.
Common symptoms include rash, fever, cough, runny nose and red, watery eyes, according to the state Department of Health. Severe complications include pneumonia and encephalitis, and the disease can be deadly. No deaths have been reported in Pennsylvania or in the U.S. so far this year. Last year, CDC data show three deaths nationwide.
Multiple vaccinations are required to attend school in Pennsylvania — public, private or parochial. Exemptions must be submitted in writing one time based on “religious or strong moral or ethical conviction.”
To enter grade school, students must have two doses of the MMR vaccine among other vaccinations against diseases like polio, whooping cough and, if they haven’t contracted it yet, chicken pox.
“If nine out of 10 people got vaccinated, we’d be alright, and it wouldn’t spread,” Dr. Mark Shelly, an infectious disease physician at Geisinger in Danville, told The (Sunbury) Daily Item last month. “Now we have a little spark, and Pennsylvania is showing up as an active outbreak. We went from zero to too much. It’s hard to put that one back in the bottle. It finds communities with low vaccination rates and spreads.”
August counts beat July
The pace of the spread in Pennsylvania is uneven but hastening, as are hospitalizations, according to data from the state Department of Health.
The seven-day case count stood at 61 on Friday. It was 66 on Wednesday and 57 on Monday.
Hospitalizations this year reached 52 on Friday compared to 46 on Wednesday and 38 on Monday. All but one hospitalization for measles this year has occurred since the start of April.
For the new cases across the past week, 1 in 3 involved minors under age 18.
The age group hit hardest, however, has been from ages 25 through 49. That demographic accounted for 107 cases on the year so far, including 83 since July 1, a figure that had stood at 58 on Monday.
Halfway through August, this month’s case count of 113 has already surpassed that of all of July, 95. There were 48 cases confirmed in June; 25 in May.
The hotspot for measles is Lancaster County, the epicenter of the current outbreak. The county totaled 161 cases on the year, as of Friday. The three counties with the next highest cases all border Lancaster, but all have substantially lower counts year to date — Chester, 37; Lebanon, 20; York, 15.
Mifflin County followed with 14 cases; Northumberland, 7; Centre, 6; Berks, Clearfield, Indiana, Jefferson, Perry, Snyder, 4; Dauphin, Montgomery, 3; Clarion, Lehigh, 2; Bedford, Huntingdon, 1.
If a county isn’t listed above, there are no confirmed cases.
Nationally, the spread of measles is at a level not seen since 1991, the end of a three-year epidemic that saw more than 55,000 cases. As of Friday, there were 2,556 cases reported by the CDC — 93% of whom were unvaccinated — far beyond the 2,289 counted in all of 2025. In 2024, the total was 285.