Measles Cases Rising In Philly Region: What To Know

Measles cases are rising around Pennsylvania, and authorities across the region warning unvaccinated residents to exercise caution.

Case numbers are up to 104 in Pennsylvania thus far in 2026, according to the Pennsylvania Department of Health.

Officials said they expect rates to continue to grow.

"We also expect more cases in the future, so here is some advice," the Chester County Health Department shared this week. "Unvaccinated children under 5, especially infants, pregnant women, and immunocompromised individuals should remain aware of increasing cases and make informed choices about local travel and socialization.

Chester County itself has had five cases this year. Nearby communities account for the bulk of statewide cases, with 55 in Lancaster County and 20 in Lebanon County. Montgomery (3), Berks (3), Dauphin (2), Northumberland (6), York (2), and Lancaster (8) have also confirmed measles cases this year.

The 104 statewide cases thus far already far outstrips 2025's numbers, when 16 cases were found in Pennsylvania.

The Philadelphia Department of Health said that a person passed through Philadelphia International Airport with measles on the Fourth of July. While unvaccinated individuals who passed through the airport were urged to monitor for any symptoms, city officials clarified days later that there are no "active" cases in Philadelphia.

Related covereage: Traveler With Measles Went To Philly Airport On Fourth Of July

Measles was also detected at a wastewater treatment plant in Delaware County on June 9 and June 11, the Pennsylvania Department of Health said in a health alert. There is no evidence that measles can be transmitted through wastewater, but it serves as a reminder of the disease's presence in the region.

Measles is making a comeback around the country due to declining vaccination rates, the Centers for Disease Control says. The past few years have represented the highest concentration of measles cases in America in more than three decades.

Measles is highly infectious to those who are not vaccinated, but it is extremely rare for a vaccinated individual to contract it, according to health officials. In the highly unlikely case a vaccinated person does get measles, they usually have milder symptoms.

Symptoms of measles include cold-like symptoms, runny nose, red eyes, greyish-white spots in the mouth, fever, and more. It's transmitted most commonly through coughing and sneezing.Measles can remain infectious in the air and on surfaces for up to two hours after an infected individual leaves that area.

The MMR vaccine that provides full immunity is available at many healthcare provider offices and pharmacies.

If you develop symptoms, contact your health care provider immediately.