Surgical disinfectant vastly reduces the risk of infection and subsequent disease and death.
Lister, building on the work of Pasteur and Semmelweis, insisted that surgery and surgical equipment be cleaned with carbolic acid, an early attempt at sterilization.
Before Lister, surgeons would not change their clothes: more blood showed more experience.
Semmelweis advanced similar ideas, showing a correlation between clean hands and a lower infant mortality rate after childbirth. Doctors at the time sneered and laughed at him.
Both Lister and Pasteur also suffered from ignoramuses who did not understand their work.
Lister’s ideas eventually gained acceptance and he became a famous surgeon, with hundreds coming to his lectures. He did not try to commercialize his work beyond academic and medical progress though.
Both Listerine and Listeria are named after Lister though there is no real link.