Pennsylvania Measles Outbreak Reaches 72 Cases Among Children and Adults

The Pennsylvania Department of Health reported 84 confirmed measles cases across six counties as of June 26, 2026, marking a multi-county outbreak that began in late April. Officials attributed the surge to the spread of the contagious virus, urging healthcare providers to promptly report suspected cases and follow testing protocols to contain the outbreak.

As of June 26, 2026, the Pennsylvania Department of Health (DOH) confirmed 84 measles cases across six counties, with Lancaster County reporting the highest number at 41 cases, followed by Lebanon County with 20, Northumberland six, Berks and Dauphin two each, and York one, according to DOH records. The outbreak, described by health officials as ongoing, began in late April and has expanded from an initial cluster in Lebanon County to multiple counties in the state. Earlier reports in 2026 indicated 62 cases statewide, but the latest update reflects a significant increase, marking the largest measles surge in Pennsylvania since the early 1990s.

As of June 26, 2026, the Pennsylvania Department of Health (DOH) confirmed 84 measles cases across six counties, with Lancaster County reporting the highest number at 41 cases.

Health officials attributed the outbreak to the spread of the highly contagious measles virus, which is transmitted through respiratory droplets and airborne particles. The DOH has urged healthcare providers to promptly report suspected cases and adhere to testing protocols, including collecting throat or nasopharyngeal swabs, urine samples for rRT-PCR, and serum for measles IgM and IgG testing, as outlined in clinical advisory guidance issued in June. Providers are instructed to report suspected cases immediately by calling the DOH hotline at 877-724-3258 (877-PA-HEALTH).

The department also issued an exposure alert after a contagious out-of-state individual traveled through Adams, Clearfield, Lancaster, and York counties, advising residents who may have been exposed to monitor for symptoms such as fever, cough, runny nose, conjunctivitis, and rash, and to contact healthcare providers or the DOH hotline if symptoms develop. This travel-related exposure highlights the potential for measles to spread rapidly across counties, particularly in under-vaccinated populations.

Vaccination status among confirmed cases remains a concern. Earlier in 2026, DOH reported that none of the 32 measles patients identified at that time were known to be vaccinated, or their immunization status was unknown, suggesting vulnerability among under-immunized groups, especially school-age children. The department’s guidance stresses that routine measles-mumps-rubella (MMR) vaccination is the primary prevention tool, recommending two doses for children—first between 12 and 15 months of age and a second dose between 4 and 6 years before school entry. Adults born in or after 1957 are advised to have one or two documented MMR doses or laboratory evidence of immunity, with two doses recommended at least 28 days apart for those without documentation in outbreak settings.

In response to the outbreak, DOH and the Centers for Disease Control and Prevention (CDC) recommend additional doses beyond the routine schedule for high-risk adults and preschool children living in or traveling to affected areas. Post-exposure prophylaxis (PEP) protocols include administering the MMR vaccine within 72 hours of exposure or immune globulin within six days for individuals lacking evidence of immunity, according to clinical advisories. Health officials emphasize that exposed persons without immunity should be closely monitored for symptoms and seek immediate care if severe symptoms such as persistent fever or shortness of breath develop.

The 2026 outbreak represents a marked increase compared to previous years. DOH data show only nine confirmed measles cases statewide in 2025, distributed across Bucks, Erie, Montgomery, and Philadelphia counties. The current surge reflects a broader national trend, with the CDC reporting over 2,000 measles cases and more than 100 hospitalizations in the United States during 2026. Experts attribute this resurgence to clusters of under-vaccinated populations and increased travel-related spread, as exemplified by the recent out-of-state case passing through multiple Pennsylvania counties.

Public health efforts include heightened surveillance, clinician education, and coordinated responses among DOH, hospitals, and local health departments. The department has issued public alerts detailing county-level case counts and advising residents in affected areas to review vaccination records. Community vaccination and catch-up campaigns are underway to address under-immunization, particularly in schools where vaccination rates have declined significantly, according to local broadcast reports and health system advisories.

The Pennsylvania measles outbreak underscores ongoing challenges in controlling vaccine-preventable diseases amid shifting vaccination patterns. Health officials continue to monitor the situation closely and recommend that healthcare providers follow state and local guidance to contain transmission and protect vulnerable populations.