Pennsylvania health officials have confirmed a fourth death linked to measles, marking the state’s worst outbreak of the disease since 1992. All four measles-associated deaths reported in the US have occurred in Pennsylvania.
The Centers for Disease Control and Prevention has not included any of those deaths in its national count after the Trump administration changed the way measles fatalities are reported. Three people died from the disease in 2025.
“My thoughts are with the two families who lost loved ones to this highly contagious virus, as Pennsylvania faces the worst measles outbreak in more than three decades,” Pennsylvania Health Secretary Dr Debra Bogen said in a statement. The state has recorded nearly 700 measles cases.
Bogen said health officials were continuing to work with partners throughout Pennsylvania to contain the outbreak and prevent further deaths. That effort includes making reliable information available and expanding access to the measles, mumps and rubella vaccine, which helped keep major outbreaks under control for decades, she said.
Measles complications, including pneumonia and neurological damage, kill between one and three people for every 1,000 infections. The death announced Tuesday involved an 18-year-old resident of Mifflin county who developed encephalomyelitis, a rare and severe neurological complication. As many as one in five people infected with measles require hospitalization.
The outbreak has been concentrated in agricultural communities in Lancaster and Mifflin counties. Utah, Florida, Virginia and Texas have also reported dozens of cases, according to data tracked by Johns Hopkins University.
More than 3,300 measles cases have been reported across the US in 2026, although epidemiologists generally believe the official figures understate the true number. Measles is among the most contagious diseases known to medicine, while the MMR vaccine prevents about 97% of cases. Vaccination rates among kindergarten-age children, a key indicator of public health protection, have been gradually falling as experts warn that administration officials are creating confusion among parents.
Since taking office, US Health Secretary Robert F Kennedy Jr has reshaped federal vaccine policy and made several misleading claims about the MMR vaccine. Before joining the administration, Kennedy led an anti-vaccine advocacy group.
The US declared measles eliminated in 2000, but it remains uncertain whether that status can be maintained as outbreaks continue to spread. Worldwide, measles is still the leading cause of vaccine-preventable deaths among infants.
