Microbe Hunters

by Paul De Kruif

  At last Koch sat down, to wait for the discussion, the inevitable arguments and objections that greet the finish of revolutionary papers. But no man rose to his feet, no word was spoken, and finally eyes began to turn toward Virchow, the oracle, the Tsar of German science, the thunderer whose mere frown had ruined great theories of disease.

  All eyes looked at him, but Virchow got up, put on his hat, and left the room—he had no word to say.

  If old Leeuwenhoek, two hundred years before, had made so astounding a discovery, Europe of the Seventeenth Century would have heard the news in months. But in 1882 the news that Robert Koch had found the microbe of tuberculosis trickled out of the little room of the Physiological Society the same evening, sang to Kamchatka and to San Francisco on the cable wires that night, and exploded on the front pages of the newspapers in the morning. Then the world went wild over Koch, doctors boarded ships and hopped trains for Berlin to learn from him the secret of hunting microbes; vast crowds of them rushed to Berlin to sit at Koch's feet to learn how to make beef-broth jelly and how to stick syringes full of germs into the wiggling carcasses of guinea-pigs.

  Pasteur's deeds had set France by the ears, but Koch's experiments with the dangerous tubercle bacilli rocked the earth, and Koch waved worshipers away, saying:

  “This discovery of mine is not such a great advance.”

  He tried to get away from his adorers and to dodge his eager pupils, to snatch what moments he could for his own new searchings. He loathed teaching—that way he was precisely like Leeuwenhoek—but he was forced, cursing under his breath, to give lessons in microbe hunting to Japanese who spoke horrible German and understood less than they spoke, and to certain Americans, who couldn't by any amount of instruction, learn to hunt microbes. He started a huge fight with Pasteur—but of this I shall tell in the next chapter—and between times he showed his assistant, Gaffky, how to spy on and track down the bacillus of typhoid fever. He was forced to attend idiotic receptions and receive medals, and came away from these occasions to guide his fierce-mustached assistant Loeffler, who was on the trail of the poison-dripping microbe that kills babies with diphtheria. It was thus that Koch shook the tree of his marvelous simple method of growing microbes on the surface of solid food—he shook the tree, as Gaffky said long afterward, and discoveries rained into his lap.

  In all of his writings I have never found any evidence that Koch considered himself a great originator; never, like Pasteur, did he seem to realize that he was the leader in the most beautiful and one of the most thrilling battles of men against cruel nature—there was no actor in this mussy-bearded little man. But he did set under way an inspiring drama, a struggle with the messengers of death that turned some of the microbe-hunting actors into maniac searchers, men who went to nearly suicidal lengths, almost murderous extremes—to prove that microbes were the cause of dangerous diseases.

  Doctor Fehleisen, to take one instance, went out from Koch's laboratory and found a curious little ball-shaped microbe, hitched to its brothers in chains like the beads of a rosary—he cultivated these bugs from skin gouged out of people sick with erysipelas, that sky-rockety disease that used to be called St. Anthony's Fire. On the theory that an attack of erysipelas might cure cancer—a mad man's excuse!—Fehleisen shot billions of these chain microbes, now known as streptococci, into people hopelessly sick with cancer. And in a few days each one of these human experimental animals of his flamed red with St. Anthony's Fire—some collapsed dangerously and nearly died—and so this desperado proved his case: That streptococcus is the cause of erysipelas.

  Another pupil of Koch was the now forgotten hero, Doctor Garré of Basel, who gravely rubbed whole test-tubes full of another kind of microbe—which Pasteur had alleged was the cause of boils—into his own arm. Garré came down horribly with an enormous carbuncle and twenty boils—the tremendous dose of microbes he shot into himself might easily have finished him—but he dismissed his danger as merely “unpleasant” and shouted triumphantly: “I now know that this microbe, this staphylococcus, is the true cause of boils and carbuncles!”

  Meanwhile, at the end of 1882, when Koch had finished his virulent and partly comic wrangle with Pasteur, who was just then with prodigious enthusiasm saving the lives of sheep and cattle in France, the discoverer of the tubercle bacillus started sniffing along the trail of one of the most delicate, the most easy to kill, and yet the most terribly savage of all microbes. In 1883 the Asiatic cholera knocked at the door of Europe. This cholera had stolen out of its lurking place in India and slipped mysteriously across the sea and over desert sands to Egypt; suddenly a murderous epidemic of it exploded in Alexandria and Europe across the Mediterranean was frightened. In Alexandria the streets were still with fear; the murderous virus—no one had the slightest notion of what kind of an invisible beast it was—this virus, I say, sneaked into healthy men in the morning, doubled them into knots of spasm-racked agony by afternoon, and put them to rest beyond the reach of all pain by night.

  Then a strange race started between Pasteur and Koch, which meant between France and Germany, to search out the microbe of this cholera that flared threatening on the horizon. Koch and Gaffky went armed with microscopes and a menagerie of animals from Berlin; Pasteur—who was desperately busy struggling to conquer the mysterious microbe of hydrophobia—sent the brilliant and devoted Ėmile Roux and the silent Thuillier, youngest of the microbe hunters of Europe. Koch and Gaffky worked forgetting to eat or sleep; they toiled in dreadful rooms cutting up the bodies of Egyptians dead of cholera; in their muggy laboratory with the air fairly dripping with a steamy heat, sweat dropping off the ends of their noses on to the lenses of their microscopes, they shot stuff from the tragic carcasses of just-dead Alexandrians into apes and dogs and hens and mice and cats. But while these rival teams of searchers hunted frantically the epidemic began to fade away as mysteriously as it came. None of them had yet found a microbe they could surely accuse, and all of them—there is a kind of twisted humor in this—grumbled as they saw death receding, their chance of trapping their prey slipping from them.

  Koch and Gaffky were getting ready to return to Berlin, when one morning a frightened messenger came to them and told them: “Dr. Thuillier, of the French Commission, is dead—of cholera.”

  Koch and Pasteur hated each other sincerely and enthusiastically, like the good patriots that they were, but now the two Germans went to the bereaved Roux and offered their help and their condolences; and Koch was one of those that carried in a plain box to its last home the body of Thuillier, this daring young Thuillier whom the miserably weak—but treacherous—cholera microbe had turned upon and done to death before he had ever had a chance to spy upon and trap it. At the grave Koch laid wreaths upon the coffin: “They are very simple,” he said, “but they are of laurel, such as are given to the brave.”

  The funeral of this first of the martyred microbe hunters over, Koch hurried back to Berlin with certain mysterious boxes that held specimens, that he had painted with powerful dyes, and these specimens had in them a curious microbe shaped like a comma. Koch made his report to the Minister of State: “I have found a germ,” he said, “in all cases of cholera. . . but I haven't proved yet that it is the cause. Send me to India where cholera is always smoldering—what I have found justifies your sending me there.”

  So Koch sailed from Berlin for Calcutta, with the fate of Thuillier hanging over him, drolly chaperoning fifty mice and dreadfully annoyed by seasickness. I have often wondered what his fellow-passengers took him for—probably they guessed that he was some earnest little missionary or a serious professor intent to delve into ancient Hindu lore.

  Koch found his comma bacillus in the dead bodies of every one of the forty carcasses into which he peered, and he unearthed the same microbe in the intestines of patients at the moment the fatal disease hit them. But he never found this germ in any of the hundreds of healthy Hindus that he examined, nor in any animal, from mice to elephants.

  Quickl
y Koch learned to grow the comma bacillus pure on beef-broth jelly, and once he had it imprisoned in his tubes he studied all the habits of this vicious little vegetable, how it perished quickly when he dried it the least bit, how it could sneak into a healthy man by way of the soiled linen of patients that had died. He dredged this comma microbe up out of the stinking water of the tanks around which clustered the miserable Hindus' huts—sad hovels from which drifted the moans of helpless ones that were dying of cholera.

  At last Koch sailed back to Germany, and here he was received like some returning victorious general. “Cholera never rises spontaneously,” he told his audience of learned doctors; “no healthy man can ever be attacked by cholera unless he swallows the comma microbe, and this germ can only develop from its like—it cannot be produced from any other thing, or out of nothing. And it is only in the intestine of man, or in highly polluted water like that of India that it can grow.”

  It is thanks to these bold searchings of Robert Koch that Europe and America no longer dread the devastating raids of these puny but terrible little murderers from the Orient—and their complete extermination from the world waits only upon the civilization and sanitation of India. . .

  8

  From the German Emperor's own hand Koch now received the Order of the Crown, with Star, but in spite of that his countrified hat continued to fit his stubbly head, and when admirers adored him he only said to them: “I have worked as hard as I could. . . if my success has been greater than that of most. . . the reason is that I came in my wanderings through the medical field upon regions where the gold was still lying by the wayside. . . and that is no great merit.”

  The hunters who believed that microbes were the chief foes of man, these men were brave, but there was careless heroism too among some of the ancient doctors and old-fogey sanitarians who thought that all this new stuff about microbes was claptrap and nonsense. Old Professor Pettenkofer of Munich was the leader of the skeptics who were not convinced by Koch's clear experiments, and when Koch came back from India with those comma bacilli that he was sure were the authors of cholera Pettenkofer wrote him something like this: “Send me some of your so-called cholera germs, and I'll show you how harmless they are!”

  Koch sent him on a tube that swarmed with wee virulent comma microbes. And so Pettenkofer—to the great alarm of all good microbe hunters—swallowed the entire contents of the tube. There were enough billions of wiggling comma germs in this tube to infect a regiment. Then he growled his scorn through his magnificent beard, and said: “Now let us see if I get cholera!” Mysteriously, nothing happened, and the failure of the mad Pettenkofer to come down with cholera remains to this day an enigma, without even the beginning of an explanation.

  Pettenkofer, who was foolhardy enough to try such a possibly suicidal experiment, was also sufficiently cocksure to believe that his drinking of the cholera soup had settled the question in his favor. “Germs are of no account in cholera!” shouted the old doctor. “The important thing is the disposition (whatever that means) of the individual!”

  “There can be no cholera without the comma bacillus!” said Koch in reply.

  “But I have just swallowed millions of your alleged fatal bacilli, and have not even had a cramp in my stomach!” came back Pettenkofer in rebuttal.

  As it is so often the case, alas, in violent scientific controversies, both sides were partly right and partly wrong. Every event of the past forty years has shown that Koch was right when he said that people can never have cholera without swallowing his comma bacillus. And the years that have gone by have revealed that Pettenkofer's experiment pointed out a mystery behind the curtains of the unknown, and these obscuring draperies have not now even begun to be lifted by modern microbe hunters. Murderous germs are everywhere, sneaking into all of us, yet they are able to assassinate only some of us, and that question of the strange resistance of the rest of us is still just as much an unsolved puzzle as it was in those days of the roaring eighteen-eighties when men were ready to risk dying to prove that they were right.

  For, make no mistake, Pettenkofer walked within an inch of death; other microbe hunters have since then swallowed cultures of virulent cholera microbes by accident—and died horribly.

  But we come to the end of the great days of Robert Koch, and the exploits of Louis Pasteur begin once more to push Koch and all other microbe hunters into the background of the world's attention. Let us leave Koch while his ambitious but well-meaning countrymen prepare, without knowing it, a disaster for him, a tragedy that, alas, has partly tarnished the splendor of his trapping of the microbes that murder animals and men with anthrax and cholera and tuberculosis. But before you read the perfect and brilliant finale of the gorgeous career of Pasteur, I beg leave to remove my hat and make bows of respect to Koch—the man who really proved that microbes are our most deadly enemies, who brought microbe hunting near to being a science, the man who is now the partly forgotten captain of an obscure heroic age.

  5. PASTEUR:

  And the Mad Dog

  1

  Do not think for a moment that Pasteur allowed his fame and name to be forgotten in the excitement kicked up by the sensational proofs of Koch that microbes murder men. It is certain that less of a hound for sniffing out microbes, less of a poet, less of a master at keeping people wide-eyed with their mouths open, would have been shoved off into a fairly complete oblivion by such events—but not Pasteur!

  It was in the late eighteen-seventies—Koch had just swept the German doctors off their feet by his fine discovery of the spores of anthrax—that Pasteur who was only a chemist, had the effrontery to dismiss with a grunt, a shrug, and a wave of his hand, the ten thousand years of experience of doctors in studying and fighting diseases. At this time, in spite of Semmelweis, the Austrian who had proved child-bed fever was contagious, the Lying-in hospitals of Paris were pest-holes. Out of every nineteen women who went hopeful into their doors, one was sure to die of child-bed fever, to leave her baby motherless. One of these places, where ten young mothers perished in succession, was called the House of Crime. Women hardly dared to trust themselves to the most expensive physicians; they were beginning to boycott the hospitals. Large numbers of them—with reason—no longer cared to risk the grim danger of having babies. Even the doctors themselves—accustomed though they were helplessly but sympathetically to preside at the demise of their patients—even the physicians themselves, I say, were scandalized at this dreadful presence of death at the birth of new life.

  One day, at the Academy of Medicine in Paris, a famous physician was holding an oration, with plenty of long Greek and elegant Latin words, on the cause—alas, completely unknown to him—of child-bed fever. Suddenly one of his learned and stately sentences was interrupted by a voice bellowing from the rear of the hall:

  “The thing that kills women with child-bed fever—it isn't anything like that! It is you doctors that carry deadly microbes from sick women to healthy ones. . .!” It was Pasteur who said this; he was out of his seat; his eyes flamed excitement.

  “Possibly you are right, but I fear you will never find that microbe––” The orator tried to start his speech again, but by this time Pasteur was charging up the aisle, dragging his partly paralyzed left leg behind him a little. He reached the blackboard, grabbed a piece of chalk and shouted to the annoyed orator and the scandalized Academy:

  “You say I will not find the microbe? Man, I have found it! Here's the way it looks!” And Pasteur scrawled a chain of little circles on the blackboard. The meeting broke up in confusion.

  Pasteur was in his late fifties now, but he was still as impetuous and enthusiastic as he had been at twenty-five. He had been a chemist and an expert on beet-sugar fermentations, he had shown the vintners how to keep their wines from spoiling, he had rushed from this job into the saving of sick silkworms, he had preached the slogan of Better Beer for France and had really made the French beer better; but during all these hectic years while he was doing the life work
of a dozen men Pasteur dreamed about the tracking down of microbes that he knew must be the scourges of the human race, the authors of disease.

  Then suddenly he found Koch had done the trick ahead of him. He must catch up with this Koch. “Microbes are in a way mine—I was the first to show how important they were, twenty years ago, when Koch was a child. . . ” you can imagine Pasteur muttering. But there were difficulties in the way of his catching up.

  In the first place, Pasteur had never felt a pulse or told a bilious man to stick out his tongue, it is doubtful if he could have told a lung from a liver, and it is certain that he did not know the first thing about how to hold a scalpel. As for those cursed hospitals—phew! The smell of them gave him nasty feelings at the pit of his stomach, and he wanted to stop his ears and run away from the moans that floated down their dingy corridors. But presently—it was ever the way with this unconquerable man—he got around his medical ignorance. Three physicians, Joubert at first, and then Roux and Chamberland became his assistants; youngsters they were, these three, radicals who were Bolshevik against ancient idiotic medical doctrines. They sat worshiping Pasteur at his unpopular lectures in the Academy of Medicine, believing every one of his laughed-at prophecies of dreadful scourges caused by sub-visible bugs. He took these boys into his laboratory and in return they explained the machinery of animals' insides to Pasteur, they taught him the difference between the needle and the plunger of a hypodermic syringe and convinced him—he was very squeamish about such things—that animals like guinea-pigs and rabbits hardly felt the prick of the syringe needle when he injected them. Privately these three men swore to be his slaves—and the priests of this new science. . .