Summary For centuries, hospitals were places where patients often acquired deadly infections instead of recovering from illness. In this final installment of our Turning Points in Infectious Disease series, we trace the remarkable transformation that changed that reality. From Ignaz Semmelweis's controversial handwashing campaign in a Vienna maternity ward to Louis Pasteur's germ theory, Joseph Lister's antiseptic surgery, and Florence Nightingale's vision for cleaner, health