"As bad as a bout of real seasonal influenza is, the H1 strain was far worse. It killed two percent or more of those stricken. In 1918, postmortem examinations helped understand if it was a case of flu. The performance of those autopsies was harrowing. Influenza defiled the lungs with bloody, frothy fluid. Instead of floating, the lungs plummeted to the bottom of water buckets during autopsies. The bronchials were fluid-filled, which explains the air hunger patients experienced. They frequently died from suffocation within 24–48 hours of developing symptoms. Some died later from secondary infections."