Martha Lillard, 78, of Oklahoma, has died, according to multiple outlets. She is described as the last known U.S. polio patient living with and relying on an iron lung, a cylindrical machine that supports breathing by changing air pressure around the patient’s body. Several reports say she contracted polio at age five and spent most of her life dependent on the device. One outlet describes her living routine as sleeping inside the chamber as air pressure cycled to help her lungs function. Her death is reported as occurring on June 26, based on an online obituary referenced by The Guardian. The New York Post quotes her younger sister, Cindy McVey, saying that doctors told Lillard she was not expected to live beyond age 20. Other reports note that the iron lung became difficult to maintain as it began to break down and that the machine was too old to repair, though the outlets characterize this differently. Across sources, the central points are her long-term reliance on the iron lung and her status as the last known American patient using one.