Two people who were not vaccinated against measles died of the disease in Pennsylvania, public health officials said on Tuesday—these are the first measles fatalities in the state in 35 years. The deaths have come as the number of measles cases across the U.S. has exploded, with 36 outbreaks recorded so far this year, according to the Centers for Disease Control and Prevention.
Both people were residents of Lancaster County. State health officials said no other details would be released to protect the privacy of the victims and their families.
So far, 2026 has seen 2,777 confirmed cases of measles, an increase from 2,289 cases for the whole of 2025, according to the CDC. This year the Pennsylvania Department of Health has reported 393 cases so far; last year Pennsylvania reported just 16 infections.
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Measles is a preventable disease; the combined measles, mumps and rubella (MMR) vaccine effectively protects against infections—in fact, it has done such a good job of lowering measles incidence that, in 2000, the U.S. was declared to have eliminated the disease entirely. Now, as vaccine rates drop as a result of increased skepticism toward the shots, infections are back on the rise, and public health experts expect the nation will soon lose its elimination status.
That matters for public health: Measles is the most contagious human virus we know of. It has a fatality rate of one to three deaths per 1,000 cases in the U.S. And it can cause severe health issues, including pneumonia and brain swelling. Some 20 percent of people who contract the disease require hospitalization. Children and pregnant women are among the most at risk of severe disease; measles can also harm unborn fetuses.
Pennsylvania’s secretary of health Debra Bogen encouraged residents to get vaccinated against the disease in a statement. Nationwide, inoculations have been declining: New data from the CDC show the proportion of kindergarteners who received the MMR vaccine has fallen from 95 percent to 92.4 percent over the past decade.
“Because measles was largely eliminated in the Commonwealth for more than three decades, people are not familiar with this disease and don’t fully understand the potential severity of the illness,” Bogen said. “We want to ensure every Pennsylvanian has the information they need to protect themselves, their loved ones and their communities. As a physician, I want to make sure that people understand that the MMR vaccine is safe and provides the best protection we have against measles.”
The two deaths from measles were confirmed just weeks after President Donald Trump signed an executive order aimed at altering the childhood vaccine schedule, particularly by splitting the MMR vaccine into three separate shots. When announcing the order, Trump falsely claimed the MMR vaccine can be “lethal.” Members of his own administration made efforts to walk the pronouncement back: In an interview on Sunday, Centers for Medicare and Medicaid Services administrator Mehmet Oz said the MMR shot is not, in fact, “a lethal vaccine.” The overwhelming evidence shows the MMR vaccine is safe and effective, with a very low risk of serious side effects.
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