Electron microscope image of a measles virus particle. (Cynthia Goldsmith/Centers for Disease Control and Prevention, via AP, File)

Electron microscope image of a measles virus particle. (Cynthia Goldsmith/Centers for Disease Control and Prevention, via AP, File)

Pennsylvania has announced its third measles-related death in less than three weeks. A local coroner says the 40-year-old woman was unvaccinated.

(Image credit: Cynthia Goldsmith/Centers for Disease Control and Prevention via AP)