When people speak of the influence of Louis Pasteur they often delimit it to the actual breakthroughs which he directly presided over. Though enormous in its scope, limiting Pasteur's achievements to just these does not do him justice. Not only did Pasteur discover a great many things (germ theory of disease, rabies vaccination, anthrax vaccination, pasteurization, the falsehood of spontaneous generation) his discoveries provided a green light for others to follow in his path--indeed he overtly cultivated a band of Pasteurians who pushed the field further and to whom we all owe a debt of gratitude.
Of the Pasteurians, one in particular deserves special mention and consideration: Alexandre Yersin, the subject of a recent fictionalized biography entitled Plague and Cholera written by Patrick Deville.
Fictionalized biographies are tricky as the author must balance presenting a plot while staying somewhat bounded by actual events in the subject's life and I believe Deville accomplishes this expertly.
Yersin is chiefly remembered today for his discovery of the plague bacillus, which today bears his name. This story of Yersin's discovery, in spite of the odds tilted in favor of Kitasato a rival from the Koch Institute, was one I was familiar with but I had little knowledge of Yersin's life outside this episode and upon learning of it my admiration for his genius has grown.
Yersin was a true polymath who excelled and made advancements not just in microbiology but in botany, agriculture, geography, and many other fields. He basically had to be dragged from his hobbies in order to solve infectious disease problems, which he did in a manner that makes it look easy before returning to his hobbies. He is portrayed as a solitary, independent-minded man--a theme of many of the lives of innovators and geniuses--whose fascination with the world was never-ending.
My favorite quote from the book is a great description of the Pasteurians and those who study and treat infectious diseases to this day:
"They are daredevils, too, adventurers, because in that day and age there is as much danger in getting close to infectious diseases as in taking off in an aircraft made of wood. A crowd of loners."
Never awarded a Nobel Prize, Yersin's life serves as an exemplar of a genius at work at the relentless pursuit of understanding. I highly recommend Plague and Cholera.
