A fourth death has been linked to measles in Pennsylvania, the state health department said Tuesday.
All four deaths have been reported in the last month, as Pennsylvania’s measles outbreak continues to grow. They are the first deaths associated with measles in the state in 35 years.
In all of last year, the U.S. recorded three measles deaths.
Pennsylvania’s health department said in a press release Tuesday that the two people who died most recently were from Jefferson and Mifflin counties. Both were unvaccinated, the department said.
The Mifflin County coroner said Tuesday that an 18-year-old resident died “due to complications of measles,” specifically, a rare and severe neurological condition that causes inflammation in the brain. The Jefferson County resident was a 40-year-old woman with asthma and severe lung disease who died on Saturday, the county coroner previously reported.
The two deaths in Lancaster County were in infants: a newborn who died shortly after birth and a 6-week-old. The county coroner has said he believes measles was only the cause of death for the 6-week-old baby. In the case of the newborn, the coroner said he found evidence of the measles virus in the infant’s lung tissue but considered the cause of death to be an internal hemorrhage and “traumatic rupture” of the spleen.
The first dose of the measles, mumps and rubella (MMR) vaccine is typically given at around 1 year, so neither infant had been eligible to receive it. Two doses offer 97% protection against measles, usually for life (the second is given at around age 5).
The Pennsylvania health department considers a death to be “measles associated” if there is clinical evidence of a measles infection, a positive laboratory test and if the death occurred within 30 days of symptoms starting. It also takes into account the person’s medical records and whether they were exposed to measles prior to their death.
The department said in a press release that the two latest deaths were linked to measles after rigorous investigations involving the county coroners’ offices. The two infant deaths involved similar investigations, the department said.
Nearly 700 measles cases have been reported in Pennsylvania this year. State officials have tied the outbreak to falling vaccination rates. Nationwide, the Centers for Disease Control and Prevention has confirmed 3,294 measles cases as of Sept. 10.
The CDC has not yet confirmed any of the deaths reported in Pennsylvania and states on its website that it does not have any death records from 2026 indicating measles is the underlying cause. Traditionally, the CDC has accepted death reports like Pennsylvania’s from state health departments; the discrepancy represents a significant departure from the way the agency has operated in the past.
CDC Director Erica Schwartz said Monday that Pennsylvania, unlike other states with measles outbreaks, had not requested the CDC’s assistance.
However, the Pennsylvania health department said it “maintains a strong working relationship with the professional staff at the CDC.” It also said it submits death records to the CDC’s National Center for Health Statistics “daily,” including for the recent measles-associated deaths.
Last month, the deaths of the infants in Lancaster County ignited a flurry of misinformation online, as well as political sparring between Pennsylvania Gov. Josh Shapiro and Health Secretary Robert F. Kennedy Jr. Shapiro accused Kennedy of spreading falsehoods about vaccines, while Kennedy suggested the deaths may have been “fabricated” and that Shapiro was seeking to profit from them politically.
Anti-vaccine activists commonly argue that testing positive for measles does not necessarily mean someone died from the virus if a secondary illness or injury was involved. However, doctors say measles is still the underlying cause in many of those cases, since patients would not have died otherwise.
