First penicillin shot: Feb. 12, 1941

Although the bacteria-fighting power of mold had been accidentally discovered by Scottish scientist Alexander Fleming 13 years earlier, it wasn't until 1940 that a team of doctors at Oxford University began successfully testing a new drug called penicillin on mice. By early 1941, they were ready to try it on a human.  On this day in 1941, Dr. Howard Florey, the head of the team, injects penicillin into a 43-year-old policeman named Albert Alexander.  A few months earlier, Alexander had scratched his face with a thorn from a rose and it had developed into a horrific infection and blood poisoning that covered his head with abscesses so virulent that he had to have an eye removed.

The penicillin has an immediate effect.  Alexander's temperature returns to normal and he regains his appeitite. But the doctors have only a limited supply and, although they are able to prolong the treatment by extracting penicillin from Alexander's urine, they soon run out.  The patient's condition worsens and on March 14 he dies.

Of the next five patients treated with penicillin, four recover from their infections. The one who dies, a young child, is actually cured of an infection, but dies of a brain hemorrhage. By the time Allied troops land on the beaches of Normandy three years later, they're equipped with ample supplies of penicillin, which saves countless lives.