tuberculosis

tuberculosis is caused by the microorganism Mycobacterium tuberculosis, or tubercle bacillus. It was in 1882 that Robert Koch, among his many historic contributions to bacteriology, identified this as the cause of the disease, thus firmly establishing for the first time its infective nature. It has been estimated that one-third of the world's population has been infected by M. tuberculosis but only a minority, probably about 10%, go on to develop disease. Disease manifests in any number of ways, almost all of them chronic, involving practically any part of the body. The most common site involved is the lungs, where cavities are produced. When this occurs patients have a cough with sputum (which sometimes contains blood), weight loss, and fever. Those with this type of disease are the most infectious, because of the presence of the bacillus in the sputum. Animals also carry the disease; although Koch had denied the possibility, it was later realized that the bovine strain of the organism, Mycobacterium bovis, could cause human infection from cow's milk.

Historically, tuberculosis has long ranked among the most feared of diseases. Such dread is reflected in some of its alternative names, including John Bunyan's ‘Captain of all these Men of Death’, and Charles Dickens' ‘dread disease’ which capture something of the prevalence of the disease in their times. Other names conjure up images of the disease process: the term ‘consumption’ describes what happened to an individual — a progressive emaciation and wasting away. Still other terms, such ‘the King's Evil’ describe the lottery of survival (cure arising from the king's touch in medieval England). Yet tuberculosis is not only a disease of the past. Keats' ‘death warrant’ continues to haunt us. Historically tuberculosis conjures up romantic images of pale, wraith-like artists suffering lingering deaths. Literature, art, and music have all recorded and been transformed by the disease. Those who have succumbed to the disease form a veritable who's who of the artistic and political worlds and notions persist that those with artistic leanings are at greater risk from tuberculosis. As Susan Sontag noted in Illness as Metaphor, ‘tuberculosis was thought to come from too much passion, afflicting the reckless and sensual.’ Gradually, however, perceptions changed. In the US, for example, Katherine Ott noted in Fevered Lives that this ‘most flattering of all diseases’ of the 1870s was transformed, as awareness of the social associations grew in the 1880s, into a disease which was seen as the consequence of either acquired or inherited degeneracy and later came to mirror ethnic and racial fears and prejudices. Yet by the turn of the century the enthusiasm for pointing the finger at individual weaknesses was tempered by an increasing awareness that society's strictures were in part responsible. In truth, in past centuries tuberculosis was a frequent killer of people from all walks of life, not only the famous and infamous, the artistic and notorious. Those living in poverty and squalor were always most susceptible.

The sanatorium movement, which promoted wholesome rest and genteel exercise in pleasant surroundings, took off in the second half of the nineteenth century. In Britain, which borrowed the idea from Germany, the first sanatoria opened in the 1890s. Although many sanatoria in Europe catered for a select, affluent, cosmopolitan clientele (an image which persists in the popular imagination conjured up by establishments such as those at Davos in Switzerland), sanatorium treatment also, by the 1920s, became available for those unable to pay, and the average duration of stay shortened. However a decline in the sanatorium movement started with the onset of World War I and was hastened by the Depression which followed. Although there were still thousands of tuberculosis sufferers receiving care in sanatoria by the mid 1940s, the availability of effective drug treatment meant that they soon became obsolete. Removal of infectious sufferers from the community had contributed to a decrease in incidence of the disease, but for the patients in sanatoria or specialized hospitals there was no specific cure. Recovery was sometimes assisted by causing collapse of an infected lung by the introduction of air into the chest (artificial pneumothorax) or by an operation that ‘caved-in’ the overlying ribs (thoracoplasty).

The advent of drug treatment followed the discovery, by Selman Waksman in the US in 1944, that streptomycin was effective, and other drugs shortly followed. When chemotherapy from then on resulted in cure for most tuberculosis sufferers, contemporary commentators told stories largely of hope, of medicine's conquest of nature, and reflected less on societal hindrances to medicine's application. An optimistic faith in the benefits of science shone through such that it seemed merely a matter of time before this ancient scourge would be eradicated. At the time this optimism seemed well-founded: mortality rates in England and Wales, which had been falling by about 1% annually since the 1860s, declined dramatically from the mid 1940s. Death rates for respiratory tuberculosis in England and Wales were about 125/100 000 at the turn of the century, and by the 1960s had fallen to below 10/100 000. Preceding the advent of chemotherapy there had been improvements in social conditions and better identification of those with active disease, along with advances in bacteriology and in X-ray diagnosis. From the 1920s there were attempts to control bovine infection, first by certifying tuberculin tested (TT) herds, and later by heat treatment to kill bacteria in milk. Although this pasteurization had been considered as early as 1913, Britain lagged behind much of Europe and the US by more than a quarter of a century in putting it into consistent effect. A further preventative measure was the introduction in the 1950s of the BCG (Bacille Calmette Guérin) vaccination programme.

Despite the remarkable success in controlling tuberculosis in the West, the overriding optimism which followed the development of effective antituberculosis drugs in the 1940s and 1950s was somewhat premature. The disease continues to target those most marginalized and vulnerable. Each year more than 8 million people acquire tuberculosis (most of them in the developing world), and about 3 million die, including about 100 000 children, annually. In England and Wales there was concern as to why this should be, why Keats' death warrant should still be received by so many, given that we have had at our disposal for over fifty years drugs which are effective in curing the disease? The answer was known half a century ago.

‘Tuberculosis is a social disease, and presents problems that transcend the conventional medical approach. On the one hand, its understanding demands that the impact of social and economic factors on the individual be considered as much as the mechanisms by which tubercle bacilli cause damage to the human body. On the other hand, the disease modifies in a peculiar manner the emotional and intellectual climate of the societies that it attacks.’ Rene Dubos who, with his wife Jean, wrote these words in 1952, was one of the giants of twentieth-century medicine. As well as being a major figure in the development of antibacterial drugs in the US in the 1920s and 1930s, which led to the later successful antituberculous drugs, he was able, unlike so many, to see the place of tuberculosis in society and to recognize the limits of modern medicine. His words resonate through the years and perhaps are more pertinent now than ever. In 1993 the World Health Organization officially called the global threat of tuberculosis an ‘emergency’. New drug-resistant strains of the organism are spreading and modern medical approaches are failing to cure patients. In England and Wales there was a 20% increase in incidence of the disease between 1987 and 1990, weighted towards the underprivileged. Overcrowding, poverty, social alienation, increased incarceration rates in prisons, homelessness, and AIDS (the ‘deadly alliance’) are combining to overwhelm uncoordinated and under-resourced public health responses.

Perhaps nowhere have the consequences of contemporary public health failures been more obvious than in New York City. In the late 1980s and early 1990s an epidemic of this ancient disease killed hundreds of people, forcing politicians to rethink their approaches to those living on the margins of society, and provoking a response which has cost millions of dollars. As Rene Dubos knew all along, tuberculosis is as much a social and political disease as it is a medical condition.

Richard Coker

Bibliography

Coker, R. (2000). From chaos to coercion: detention and the control of tuberculosis. St Martins Press, New York.
Dormandy, T. (1999). The White Death: a history of tuberculosis. The Hambledon Press, London.
Ott, K. (1996). Fevered lives: tuberculosis in American culture since 1870. Harvard University Press, Cambridge MA.
Ryan, F. (1992). Tuberculosis: the greatest story never told. Swift publishers, Bromsgrove, Worcestershire.
Sontag, S. (1978). Illness as metaphor. Farrar, Straus and Giroux, New York.

See also infectious diseases; immunization.