A 39-year-old unvaccinated woman became the sixth measles death in Pennsylvania.

As of Friday, state health officials reported 1,136 cases across 41 counties.

As of Friday, state health officials had reported 1,136 cases in 41 counties.

Bright-colored transmission microscope image of measles virus.

An unvaccinated 39-year-old woman in Franklin County, Pennsylvania, is the sixth person to die from the highly contagious virus amid a statewide outbreak that has infected more than 1,000 people since the beginning of April.

The woman died on Saturday, October 10, according to an advisory posted on social media by Jordan Connor. The advisory noted that the woman's death met the definition of a measles death as determined by the state health department.

In an emailed statement to The Washington Post, the medical examiner's office said the cause of death was "probable acute cardiac complications due to possible complications of measles."

The five previous deaths amid the measles outbreak in the state included a newborn, a 6-week-old baby, an 18-year-old, a 20-year-old and a 40-year-old. All the deceased were not vaccinated. Two babies were too young to be vaccinated.

According to the latest measles update from the Pennsylvania Department of Health on Friday, Oct. 9, there have been 1,136 cases in the state since the start of the year, 1,124 of which are related to the current outbreak. A total of 218 people have been hospitalized. The outbreak, now covering 41 of the state's 67 counties, shows no signs of slowing. In the last week alone, 157 new cases have been reported.

A spokesman for the state Department of Health told the Post it was "aware" of the new death and was investigating. It will provide an update once the review is complete.

Measles, which was eliminated in the United States in 2000, is on the rise amid misinformation and declining vaccination rates. The number of measles cases nationwide has reached 4,080 for the year, the highest since 1991. The Pennsylvania outbreak is also the largest since that year. The United States is widely expected to lose its measles-elimination status when Pan American Health Organization (PAHO) experts meet in November to review US measles data.

Under anti-vaccine Secretary of Health Robert F. Kennedy Jr., the Centers for Disease Control and Prevention has so far included only two of the six deaths in its report. In 2025, three measles-related deaths were reported in the United States.

Beth is Ars Technica's senior health reporter. Beth holds a Ph.D. in microbiology from the University of North Carolina at Chapel Hill and attended the Communication Sciences Program at the University of California, Santa Cruz. He specializes in coverage of infectious diseases, public health and microbes.