A fourth person in Pennsylvania has died of measles, the state health department confirmed Tuesday. The latest death was an unvaccinated 18-year-old resident of Mifflin County, who developed acute disseminated encephalomyelitis (ADEM) — a rare but known severe complication of measles.
ADEM is a rapidly progressing autoimmune disorder in which measles-triggered inflammation strips away the protective myelin sheaths covering nerve cells in the brain and spinal cord. Before measles vaccines were widely used, ADEM was commonly associated with the disease.
The state health department also confirmed the death of an unvaccinated 40-year-old woman in Jefferson County. The two deaths will be added to the state's outbreak dashboard Wednesday. Pennsylvania had previously reported two deaths in Lancaster County — both infants, a newborn boy and a 6-week-old girl, both too young to be vaccinated.
Pennsylvania has recorded 693 measles cases across 38 counties this year, with 133 hospitalizations and 99 new cases reported in the past seven days alone. "Pennsylvania faces the worst measles outbreak in more than three decades," said Health Secretary Debra Bogen.
The deaths arrive amid continued controversy over federal measles data reporting. The CDC has changed how it counts measles deaths, now requiring records to come through the National Center for Health Statistics rather than state and local health officials. Health Secretary Robert F. Kennedy Jr. has disputed deaths and spread misinformation about the MMR vaccine, and reportedly ordered the CDC director to exclude reports of the two babies' deaths.
Even with these reporting changes, the CDC is still tracking nearly 3,300 measles cases nationally this year — higher than last year's record of 2,289 cases and the highest total since 1991, when the US recorded 9,643 cases. The US declared measles eliminated in 2000 after blocking domestic transmission for 12 months through high vaccination rates, but with vaccination rates slipping well below the 95 percent target, measles is roaring back.
