Pennsylvania measles outbreak surpasses 1,000 cases

Pennsylvania’s measles outbreak has surpassed 1,000 confirmed cases, overtaking South Carolina’s 997-case outbreak as the largest in the United States in more than three decades. The Pennsylvania Department of Health reported 1,004 cases Monday, including 198 hospitalizations. Five people in the state have died after contracting measles.

The outbreak began in April. Lancaster County has recorded 391 cases, the most of any county in the state, according to figures cited by The Guardian. The county is home to sizeable Amish and Mennonite populations. The Guardian reported that health officials attributed the outbreak to low vaccination rates.

Nearly a third of Pennsylvania’s cases have been in children, NBC News reported, and 18% of pediatric patients have required hospitalization. Dr. Evan Shirey, a pediatric infectious disease physician at Penn State Health Golisano Children’s Hospital, said dehydration has been common among babies and younger children. Doctors have also seen liver problems, secondary bacterial infections and, in some children, severe and irreversible neurological damage caused by brain inflammation.

“In some of these cases, it’s a child who can’t recognize their own mother, who’s disoriented and confused,” Shirey said.

According to NBC News, those who died include two babies, a teenager with severe brain inflammation and a 40-year-old woman with a history of asthma. One baby was a newborn whose mother went into labor a month early. Few details have been released about the fifth person, who was unvaccinated and lived in Lancaster County.

The Guardian reported that Pennsylvania’s figures are not included in a Centers for Disease Control and Prevention count amid an ongoing dispute between Governor Josh Shapiro and U.S. Health Secretary Robert F. Kennedy Jr. over how to classify measles-related mortality. Kennedy has questioned whether the state’s recorded fatalities were directly caused by measles. The CDC lists two measles deaths nationwide this year, according to The Guardian.

Shapiro has expanded access to the measles, mumps and rubella vaccine in affected communities. “Measles does not care about your county, your faith, or your social circle,” he said in August, urging residents to discuss concerns with a health care provider.

Pennsylvania has administered 8,843 MMR doses in response to the outbreak, its health department said Monday. An NBC News investigation found that 88.5% of Pennsylvania kindergartners had received the vaccine in 2024, below the 95% coverage considered necessary to prevent outbreaks.

Dr. John Goldman, an infectious disease expert at the University of Pittsburgh Medical Center, said vaccinations had increased but not enough to stop the outbreak. “I would bet that this goes on for at least another three to six months,” he said.

South Carolina’s outbreak ended in April. Health officials there credited a surge in vaccinations: Nearly 15,000 MMR doses were given in the area where cases were concentrated, an 82% increase over the previous year.

Measles cases have also been reported in neighboring states. Ohio had recorded 210 cases and 13 hospitalizations as of Thursday, NBC News reported. The Guardian reported that New York Governor Kathy Hochul declared a state of emergency over measles and that the CDC had counted 3,887 confirmed U.S. cases as of October 1.