Every Radnor Township public school cleared the CDC's 95% measles vaccination threshold for herd immunity, according to state data released for the first time at the individual school level. One school sits near the edge.
Ithan Elementary in Bryn Mawr posted the district's lowest immunization rates for the 2025-26 school year: 95.1% of kindergarteners vaccinated against measles and 93.9% protected against Hepatitis B. With about 82 kindergarteners enrolled, those percentages translate to roughly four or five children missing their MMR shots and five or six without the Hepatitis B vaccine, Patch reported.
The remaining four district schools — Radnor Elementary, Wayne Elementary, Radnor Middle School and Radnor High School — all exceeded 95% MMR coverage.
Why it matters now
The first day of school for Radnor Township School District is Monday, Aug. 24. Under Pennsylvania law, families have five days after school starts to show proof of immunization or an appointment to get vaccinated. After that deadline, unvaccinated students must leave school until they comply.
That timeline takes on added weight as Pennsylvania's measles outbreak grows. The state has confirmed 307 cases in 2026, with 162 in Lancaster County and 37 in Chester County, according to LancasterOnline. Delaware County has reported zero confirmed cases.
Every confirmed measles patient in Pennsylvania this year was not fully vaccinated, state Health Department press secretary Neil Ruhland told LancasterOnline on Aug. 17. Of those infected, 52 people (17%) have been hospitalized.
Statewide context
The Pennsylvania Health Department published the school-level data on July 31 in response to the outbreak. Previously, vaccination rates were available only at the state and county levels.
Statewide, 93% of kindergarteners received both MMR doses in 2025-26, compared to 97% of 12th-graders, according to City & State PA. Radnor's elementary schools outpace that state average, but the gap between Ithan's 95.1% and the 95% herd-immunity line is slim.
Delaware County Health Department Director Lora Siegmann Werner urged residents to act in a July 23 statement, ahead of the county's back-to-school immunization campaign launch on July 27. "Measles can be dangerous, and it is vital that Delaware County residents receive their MMR vaccines so that we can protect our most vulnerable populations," Werner said.
The county's Wellness on Wheels mobile clinic is offering vaccines to residents ahead of the school year.
What's next
The Radnor Township School Board updated its communicable diseases and immunization policy (Policy 203) at its May 26 meeting, adding language on immunization timelines for transfer and foster students. The board's next regular business meeting is Tuesday, Aug. 25, one day after school opens.
As we reported Aug. 13, Haverford and Radnor students face a tight window to meet the state's immunization requirements. Families needing vaccines can contact their pediatrician, a local pharmacy or the Delaware County Health Department's immunization clinics listed at delcopa.gov/health/immunizations.
