Microbe Hunters

When I was a kid, my grandfather gave me a copy of Microbe Hunters. It had inspired him into science as a youth--he became a chemist--and it ended up doing the same for me. I read about the lives and discoveries of self-made scientists of long ago and thought, I want to do that. The book gave me the feeling that I could go into my backyard or garage and make a discovery that nobody else ever had, if I poked around curiously and meticulously enough. It was exciting.  

My grandfather has since passed away, but I was thinking about my him recently and it led me to reread Microbe Hunters. It is both exactly what I remembered, and a completely different book.  

Whenever I read the book as a kid (I read it many times), my favorites were the two chapters about Louis Pasteur. De Kruif writes in excited language and he is liberal with fictional conversations which bring the scientists to life. He also emphasizes the importance of each individual scientist's genius (annoying to me today; inspiring to me as a kid). This was great for helping a young girl like me to actually picture Pasteur running around in fields collecting blood samples from anthrax-infected sheep, and cooking these samples into poisonous stew to be used in clever new experiments in the hunt for a cure.  

The result: Pasteur's stories were relatable. I'd tinkered with test tubes! I'd used a microscope! I loved running around outside! I saw sheep all the time, just outside of town! I could do what Pasteur did! Only as an adult do I understand how powerful—and so rare—that kind of relatable scientific inspiration can be, especially for a girl. In fact, today I can think of only a small handful of other childhood experiences that inspired me to science the way this book, and these chapters in particular, did. 

Alas, I've become cynical in the intervening 30 years. My re-read confirmed that I remembered the facts of Pasteur's discoveries reasonably well. What I did not notice as a child was what a jerk he was. True or not, the fictional Pasteur of de Kruif's book is a dick. He's petty, he's jealous, he disparages colleagues, much of his scientific progress is driven by personal rivalries...he's even challenged to a duel at one point (he declined).  

Reading as an adult, I'm irritated by the terrible behavior of a childhood hero. One does not need to be a jerk in order to be great at science, or at anything else. To read this book, though, and to look around at today's popular heroes, you get the message that petty, aggressive, and generally obnoxious behavior is a plus. As a kid this didn't bother me because I assumed that it was historical. Surely the world was different in 1990! Sadly, though duels have been replaced by office politics and PR machinery, the acceptance of terrible behavior in the name of greatness persists. We've all seen mediocre ideas accepted over better ones in the office or lab because their advocates were more aggressive. We all know what Steve Jobs was like, and we celebrate him for it. 


One element of the book that I did remember clearly was how the link between scientific discovery and technological advancement was crude (and may still be, but I know next to nothing about how drug trials work today). Many of the book's chapters focus on the dazzling scientific discoveries of the microbes or transmission models for various ailments: syphilis, anthrax, yellow fever, malaria, tuberculosis, sleeping sickness. These breakthroughs were usually followed by wild promises of the elimination of the disease from humankind within a few years. These promises were then followed by poorly-designed treatments or hastily-concocted vaccines that killed hundreds or thousands of people (but did save some, too, and did lead to further progress in the quality of treatment). 

My favorite example of this from the book is Paul Ehrlich's discovery of a chemical compound to cure syphilis. He had the seemingly-crazy idea that there must exist chemical compounds that would kill the bacteria inside humans without harming the humans themselves. So he ran hundreds of lab tests in which he injected various compounds into infected lab animals. With limited methodology but many inspired hypotheses, he tried hundreds of different compounds.

After seven years of experiments, Ehrlich found a compound that could cure syphilis. He called it Salvarsan. It was based on the deadly poison arsenic. It did cure syphilis, but it also killed a non-trivial number of its recipients, and it had awful side effects. It became a popular and widespread treatment nevertheless, being better than nothing. Reading about this today, the parallel between Salvarsan and modern cancer chemotherapy springs to mind. And it's a hopeful parallel. Just as syphilis is little more than a rare nuisance today, perhaps in 100 years we will say the same about cancer, and shake our heads in disbelief at the barbarism and relative impotence of today's treatments.  

De Kruif couldn't draw the parallel to today's chemotherapy, though, because he was writing in the 1920's. Microbe Hunters was published in 1926, another fact I didn't consciously grasp as a child. The book is now nearly 100 years old! I was startled to realize this, because it meant that half of the discoveries were less than 40 years old as de Kruif was writing about them. He calls Salvarsan a "magic bullet", using the popular language of the time. Even as a kid, I realized that Salvarsan was an antibiotic. But that term wasn't coined until more than a decade after the publication of the book! 

To de Kruif and his original audience, the discovery of Salvarsan was the equivalent of, say, today's anti-retroviral drugs. They would have remembered the days when syphilis was a death sentence, just as readers today can remember when a diagnosis of HIV/AIDS meant the same. Realizing this helped me understand why de Kruif's language is so excited throughout. He was living in a world that had only very recently begun to enjoy the vast benefits of the discoveries he was describing. I look at his optimism for the future and compare it to the cynicism and mistrust that surrounds modern discussions of technology, and I envy de Kruif a bit. 

Some things don't change, though. There's one passage in which de Kruif describes Elie Metchnikoff's discovery of an ointment to treat syphilis, at the turn of the twentieth century: 

Moralists—and there were many doctors among these, mind you—raised a great clamor against these experiments of Metchnikoff. "It will remove the penalty of immorality!" said they, "to spread abroad such an easy and a perfect means of prevention!" But Metchnikoff only answered: It has been objected that the attempt to prevent the spread of disease is immoral. But since all means of moral prophylaxis have not prevented the great spread of syphilis and the contamination of innocents, the immoral thing is to restrain any available means we have of combating this plague."  

Replace syphilis with unwanted pregnancy, and you've got the same debate we are still having today, particularly in election years. What an infuriating waste of a century of energy. 

Despite my own captivation by this book, I am not sure whether I would recommend it to all young scientists-to-be today. It lit a spark in me, for sure, but I can also imagine lots of scientifically-inclined young minds for whom it might be a laborious read. It also contains some appalling racism, in both language used to describe people and in the way human subjects were chosen for experimentation. The book underscores the presumption of the time that science is the exclusive realm of the white and male.  

I'm attached to the book anyway, though. It came to me though my grandfather, who also inspired and supported my love of science and learning in many other ways and with enormous affection and kindness. So, when my own children are old enough, I will be excited to share Microbe Hunters with them. I hope it sparks discussions about science and medicine and culture and changing notions of equality. Most interestingly, I'll be curious to see whether they too will be drawn in by a 100-year-old book about "modern" science.