In which field of science did Alexander Fleming specialize?

I thought he was the one I read about in college. Think about the many people who used to die from even the simple minor infections! And all the people operated on by doctors without these wonder drugs!

PerkyLin, Another thing we take for granted that we should be thankful for.

Amazing Scott 👏🏽👏🏽👏🏽 bravo! And I am allergic to Penicillin 😬

PerkyLin, Or from Dr's not washing their hands