The Remedy

by Thomas Goetz

  Few of the men there, whether friends or rivals, knew exactly what Koch would present that evening. Aside from his lecture’s vague title, “On Tuberculosis,” he had given up nothing in advance. But such was his reputation that every scientist in Berlin wanted to see what the wily Koch would come up with next.

  With Koch’s preparations complete, the doors were closed and the crowd settled down. Koch, clearly nervous, his spectacles perched on his nose, shuffled his papers. “Die Tuberculose,” he said, and then began to read his paper slowly, with frequent pauses, not for effect but as if to find his place. Later, Loeffler recalled the scene. “Koch was by no means a dynamic lecturer who would overwhelm his audience with brilliant words,” he said. “He spoke slowly and haltingly, but what he said was clear, simple, logically stated—in short, pure unadulterated gold.”

  Koch began by putting the disease in context, reminding his audience of the vast toll that tuberculosis had taken on humanity. “If the importance of a disease for mankind is measured by the number of fatalities it causes,” he said,

  then tuberculosis must be considered much more important than those most feared infectious diseases, plague, cholera, and the like. One in seven of all human beings dies from tuberculosis. If one only considers the productive middle-age groups, tuberculosis carries away one third and often more of these.

  Then he described his efforts to study the disease, how he had tried to isolate and identify a specific cause. The first challenge was to see the germ; in contrast to other bacteria he had worked with, Koch had found this one elusive under his scope. The usual technique, developed by Paul Ehrlich, was to stain the slide of bacteria with a drop of methylene blue dye. Typically, the cell walls of the bacteria absorb some of the dye, and the rods and spores show up in relief on the slide. But methylene blue didn’t work here—until Koch ingeniously added a second, brown dye. Suddenly, the bacteria were exposed, as if a black light had been shone upon invisible ink.

  Now that the bacteria were visible, he said, the experiments could begin. He explained how he had cultured the bacteria and then injected them into a menagerie of healthy animals. These all developed tuberculosis, one after the other, and he then began to isolate the bacteria from their blood and tissue and inoculate them into more animals. When these, too, acquired the disease, he knew that he had isolated the true cause of tuberculosis.

  Koch’s presentation was labored, even tedious. He showed his test tubes and slides. He displayed his cultures. And he explained how he had tested and retested his work. He had anticipated every critique, every concern, and worked until he had the data to refute all arguments. His presentation that evening was a catalog of experimentation and self-examination, with Koch chalking up a finding only after he had presented the exhaustive evidence that would allow him to proceed. Throughout, his face remained stern and without emotion. There was no hand waving. There were no assumptions, no insinuations. There was only evidence and explanation—and finally, an end.

  “All of these facts taken together can lead to only one conclusion,” Koch said. “That the bacilli which are present in the tuberculosis substances not only accompany the tuberculosis process but are the cause of it. In the bacilli we have, therefore, the actual infective cause of tuberculosis.”

  The statement was so simply phrased, so matter-of-fact in its delivery, that the gravity of Koch’s claim seemed almost benign. Here was Koch, who had gotten his start with jury-rigged equipment and kitchen-sink experiments, claiming to have discovered the cause of one of the most dire diseases in history. Here was Koch saying that this contagion was definitively a bacterium.

  Nobody quite seemed to know what to make of this. There was no applause, no murmuring, no debate. The crowd was simply, utterly, absolutely speechless. Ehrlich was awestruck by the thoroughness and incontrovertibility of Koch’s presentation. “I hold that evening to be the most important experience of my scientific life,” he said later.

  Some shook hands with Koch, offering him congratulations. Others moved to his materials, examining the cultures and slides under the scope. Then, finally, Virchow, the great paragon of German science, put on his hat and walked out of the room without saying a word.

  • • •

  TO GRASP THE SIGNIFICANCE OF KOCH’S DISCOVERY, WE MUST FIRST get our heads around this: To live in the nineteenth century was to experience infectious disease as a constant, to have unexplained illnesses afflict and dispatch loved ones without warning. Simply put, more people died of more things back then than do now; the death rate in London in 1850 was twenty-five per thousand—more than five times today’s death rate.

  Such an existence is, admittedly, almost inconceivable today. In the twenty-first century—in the developed world, at least—infectious disease is more a threat than a reality. In fact, we have been inoculated from the experience of contagion, the absolute routine drudgery of it, protected from the experience of a disease flourishing in our midst without any explanation, treatment, or cure. Today, few of us have much experience with infectious disease, beyond the occasional cold or flu or stomach bug.

  When a contagion does cross our consciousness, it’s either the stuff of distant Third World endemics such as malaria or, when in our midst, the stuff of front-page panics such as SARS. A sudden outbreak of disease—West Nile virus, say, or cholera or salmonella—appears to us like a breach in a force field, an aberration that we expect some authority will address and stamp out before it comes close to threatening us or our families. HIV/AIDS has killed about 620,000 Americans since the first case in 1981, roughly the same number of those who die from heart disease or cancer every year. This isn’t to minimize the grave toll of HIV/AIDS. But by historical standards, the impact demonstrates how detached we are from the experience of infectious disease and how terrifying an epidemic can be today, even for those with little risk.

  The nineteenth century, though, was a one-hundred-year dirge from one horrid epidemic to another. Six waves of cholera ravaged the globe during the century: The first killed hundreds of thousands from 1816 to 1826; the second killed 100,000 in France, 55,000 in the United Kingdom, and 150,000 in the United States; the third claimed 250,000 lives in Spain and nearly a million in Russia; and so on. There was plague, too: In the 1850s, the “third pandemic” of bubonic fever broke out in Asia, killing more than 12 million in China and India before spreading worldwide. (It took nearly fifty years to reach North America, breaking out in San Francisco’s Chinatown district in 1900.) And despite Jenner’s vaccine, smallpox would periodically take advantage of vulnerable populations and kill off thousands before officials could mount an immunization response. Yellow fever, influenza, measles—all these pulsed through growing urban populations of the 1800s, killing thousands and then stealthily retreating for a generation or two, waiting for immunity to fade, before returning to kill thousands more. All these diseases came quickly, in terms of both their attack on the human body and the speed with which they spread through a community. They were fast and terrifying, and then, after some weeks or months or at most a couple of years, they were gone.

  Tuberculosis was altogether different. It was not an epidemic but an endemic disease. It didn’t come in waves or explode through a population; its presence was constant, pervasive, and persistent. Indeed, the history of humanity is intertwined with the history of tuberculosis; it has been found in Egyptian mummies and in ancient Native American burial grounds, and it is mentioned in four-thousand-year-old Sanskrit texts from India. It likely emerged with the dawn of agriculture. Since the bacterium can survive in dust and dirt but dies under sunlight, it seems probable that its origins lie in the soil itself. (In this, it is not unlike anthrax.) From there, it was likely transmitted to humans by the milk and meat of grazing livestock. (Cow’s milk was a vector for tuberculosis until pasteurization became widespread in the early twentieth century.)

  Though it had afflicted humanity for millennia, in the nineteenth centur
y tuberculosis went on a rampage, a tide of death known at the time as the White Plague. As Koch noted in his opening remarks, the disease was the largest killer by far in the United States and Europe. At the Hôpital de la Charité in Paris, more than one-third of autopsies performed in the early 1800s found the cause of death to be TB. By the end of the century, in 1890, the registrar general of Ireland’s returns showed that nearly half of those who died between fifteen and thirty-five years of age died of consumption. This toll was particularly painful for the nascent life insurance industry. In 1865, the British Empire Mutual Life calculated that tuberculosis was responsible for more than three-quarters of company benefit payments.

  Year after year, the disease claimed a massive portion of the population, festering in families and neighborhoods and cities. It was always there, always taking lives in a steady attrition that made it seem, well, normal. To die of tuberculosis was, oftentimes, tantamount to just plain dying—it was how most people went. Charles Dickens, in 1839’s Nicholas Nickleby, captures the despondency it brought on:

  There is a dread disease which so prepares its victim, as it were, for death; which so refines it of its grosser aspect, and throws around familiar looks unearthly indications of the coming change; a dread disease, in which the struggle between soul and body is so gradual, quiet, and solemn, and the result so sure, that day by day, and grain by grain, the mortal part wastes and withers away, so that the spirit grows light and sanguine with its lightening load, and, feeling immortality at hand, deems it but a new term of mortal life; a disease in which death and life are so strangely blended, that death takes the glow and hue of life, and life the gaunt and grisly form of death; a disease which medicine never cured, wealth never warded off, or poverty could boast exemption from; which sometimes moves in giant strides, and sometimes at a tardy sluggish pace, but, slow or quick, is ever sure and certain.

  The tenacity of tuberculosis, the fact that it was “a disease which medicine never cured, wealth never warded off,” made many physicians reluctant even to try. The English physician Thomas Young explained with resignation in 1815 that it was “a disease so frequent as to carry off prematurely about one-fourth part of the inhabitants of Europe, and so fatal as often to deter the practitioner even from attempting a cure.” Writing in 1840, George Bodington, a physician who ran a sanatorium in Birmingham, England, bemoaned the general state of medical care for people with tuberculosis: “Consumptive patients are still lost as heretofore; they are considered hopeless and desperate cases by most practitioners, and the treatment commonly is conducted upon such an inefficient plan as scarcely to retard the fatal catastrophe.” Bodington himself argued vociferously that a remote, dry climate, where the patient could be free of worry, offered some hope; his evangelism marked the beginning of the sanatorium move-ment in Europe and the United States.

  All told, the pervasiveness of tuberculosis and the impotence of medicine to treat it created a specter of misery in nineteenth-century Europe and America. To live in this environment would have been always to be reminded of the presence of death. The constant cough of tuberculars, combined with the crackling sound of their lungs straining to breathe—a sound known as a rale—created a white noise of illness in European and American cities. The only consolation would have been ignorance: Until Koch’s discovery of the bacillus, being coughed on, as many inevitably were, would not have prompted much concern.

  The experience of the disease was, as Dickens described, typically a slow, dispiriting decline. Early symptoms were elusive; some cited “severe bodily or mental fatigue,” while others described “a short and insidious cough, with a feeling of lassitude, and a decline in general health.” Eventually a physician would confirm the diagnosis with his stethoscope but could offer little in the way of relief. A consumptive patient could live for years, even decades, with the disease, the cough coming and going in fits while, in the lungs, the bacteria slowly spread, eating away at the soft tissue. In its torpid pace, tuberculosis is more like the chronic diseases of today, such as heart disease or diabetes, which can take years to whittle away at the body before dealing a fatal blow.

  In the closing years of the nineteenth century, tuberculosis was at its most rapacious. One can get a sense of how ubiquitous it was by noting how many famous figures of the day died from it. Elizabeth Barrett Browning, Johann Wolfgang von Goethe, Friedrich Schiller, Henry David Thoreau, all three Brontë sisters, Anton Chekhov, Washington Irving, Guy de Maupassant, Edgar Allan Poe, Sir Walter Scott . . . The toll is so vast that there’s an entire Wikipedia entry devoted to the subject.

  Such rolls of notables convinced many that consumption had its upside. The slow, wasting nature of the disease made it fodder for romanticists and drove the plots of operas such as La Traviata and La Bohème. It infused the poetry of Keats, Shelley, and Byron. “I look pale,” Byron told a guest in Patras in 1828. “I should like to die of consumption.” “Why?” his guest asked. “Because the ladies would all say, ‘Look at that poor Byron, how interesting he looks in dying!’”

  The truth was far less beautiful and far more brutal. Nineteenth-century civilization seems to have been custom-designed for a microbe such as tuberculosis. It was, of course, the great age of industrialization, when people were pouring into European and American cities for work. To say they lived on top of one another is to be fairly literal: The average household size in 1850s England was nearly seven persons, more than double the average today.

  Inside these “fever-breeding structures,” as journalist and social reformer Jacob Riis described them, the levels of cleanliness were, by today’s standards, abysmal: Lice and bedbugs were common. Working people typically wore the same clothes for days, and for many families, soap was still a novelty. (In the United Kingdom, use of soap was about three and a half pounds per person annually in 1801 but would grow to five times that amount, nearly fifteen pounds per person, by century’s end.) With no plumbing, water was drawn and carried from local pumps and so was scarce.

  Outside, on the streets, the gutters were full of household waste and the piss and shit of animals, from humans to horses. Even in cities that did have some sewers, such as Paris, sanitation was horrendous. During the “Great Stink” in 1880, the sewer under the boulevard de Rochechouart clogged up with human excrement. The fumes were so concentrated that four men sent underground to clear the stuff died of asphyxiation. (London had its own Great Stink, in 1858, when the Thames overflowed with sewage.)

  And then there was the spit. Spitting in the nineteenth century was as routine as chewing gum is today. Clearing one’s throat and hawking the mucus onto the street was not just common; it was considered by many to be outright proper. Swallowing one’s expectorant, on the contrary, was considered unhealthy. “Why do we expectorate?” asked an editorial in The Medical Brief, an American journal. “Because the passages are filled with dead matter which the system seeks to eliminate. Nature knows no laws but her own. She directs the individual expectorate, while the profession who has charge of his physical welfare wants to force him to transfer this dead matter to the stomach to deprave the gastric juice, and further harm the system.”

  Americans, perhaps not surprisingly, were considered the worst offenders, what with their appetite for tobacco and their generally uncouth culture. Alfred Bunn, an English writer visiting the United States in 1853, observed spitting, well, everywhere:

  They spit, as a matter of course, upon floors, and even costly carpets covering them; in grates, over, or under them; in all public conveyances, all about the streets, in shops, on the decks and in the cabins of all vessels, in theatres and other places of amusement, in both Houses of Congress, all lobbies leading thereto, and all apartments connected therewith; at all tables, during all meals, in their counting-houses and stores, in passages and bedrooms, which makes it an impossibility to cross them, without either putting on slippers, or “putting your foot in it”; and as no place is sacred from pollution, of course t
hey spit in their Courts of Justice, there being no law against it.

  In truth, spitting was routine throughout the United States and Europe. Part of this was not just social but simply environmental, a consequence of cities, such as London, being covered with a pall of dust and smoke. An 1847 French medical textbook reported that “many persons, in health, every morning reject several sputa, of a grayish or blackish color; this color is owing to the smoke which collects from lamps, candles, etc., particularly in small apartments.” Indeed, the amount of spit hawked up in London every day was used as an argument against the germ theory in the months after Koch’s discovery. “When we consider the number of consumptive people who, being under no restriction, go about coughing and expectorating freely in the streets and parks of London,” wrote C. J. B. Williams of Brompton Hospital in the British Medical Journal, “we must admit that the bacilli, though ever present, are not very active in ill-doing.”

  Alas, Dr. Williams couldn’t have been more wrong. All this hawking and expectorating was, in fact, exceptionally kind to the tuberculosis microbe. When a diseased person spits (or coughs or sneezes or even talks), a cloud of saliva droplets fills the air. In each droplet are thousands of bacteria, coming along for the ride. Even when a neighbor inhales this emission, the odds of the bacteria causing infection are fairly low. The relative bulk of the cloud of droplets means that most get stuck in nasal mucus or the higher respiratory tract, never making their way to the soft spot of the lungs. But some of these droplets linger in the air, and the air evaporates the saliva. The residue, known as droplet nuclei, can continue to float in the air, ready to be drawn by some newcomer’s inhalation, and are small enough to be sucked deeply into the lungs.

  Even then, the victim isn’t yet doomed. The lungs are filled with special immune cells primed to absorb invasive bacteria and destroy them. Tuberculosis, though, is well equipped for this battle. The bacterium has a notably thick, waxy cell wall, which makes it difficult for white blood cells to penetrate and destroy the invader. Instead, the body takes a secondary defense measure: It surrounds the bacteria and locks them into nodules, known as granulomas, a kind of stalemate between bacteria and host. For 90 percent of those exposed to tuberculosis, this is as far as the bacteria will get. These cases are considered latent tuberculosis, as the disease is present but inactive; most persons will never know they harbor the germ.