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SCIENCE, SOCIOLOGY, RELIGION => Science and Technology => Topic started by: Makini on January 21, 2014, 07:55:31 AM

Title: John Snow and cholera (medicine colliding with science, politics and culture)
Post by: Makini on January 21, 2014, 07:55:31 AM
I am familiar with this story of John Snow and how he prevented cholera. It can be found in some biology text books, but more so in microbiology and epidemiology text books. And even on television, where I recently saw him being mentioned in a tv series last week and resulted in me doing some further reading on him.

While it is true that Europeans contributed a lot to modern science and technology, it is important to be cautious about the history of how such information is presented as well as the context in which these developments were made. This article is quite detailed in that regard. While the entire article is very informative, its also very 'academic'. I pulled out some parts which are below that summarizes a perspective (less romantic) on John Snow that is not usually presented.

John Snow and cholera
By Richard Barnett

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As it is usually told, the story of John Snow and cholera begins with one of those great moments that historians used to be so fond of. On the morning of 8th September 1854 a party of workmen removed the handle of a public water-pump, on what was then Broad Street in Soho. They were acting on the advice of Snow – a general practitioner and anaesthetist with rooms a few streets away. At an emergency meeting the previous evening, he had convinced the parish authorities that water from this pump was responsible for a terrible cholera outbreak, which had killed more than five hundred people in less than two weeks.

Since the 1930s many writers have woven a heroic myth around the story of the Broad Street pump. They have argued that Snow discovered the cause of cholera (which, as he himself made clear, he did not); that he saved many lives by disabling the pump (which, as we shall see, is moot); and that he revolutionised the way in which politicians, physicians and public health reformers thought about cholera (which, again, he did not).

Ever since his reappearance as a founding father of epidemiology and public health, Snow and his work on cholera have been both troublesome and enormously useful for historians of medicine like me. Studies of Snow have complicated and enriched our understanding of nineteenth-century British history, taking us to the places where medicine collided with science, politics and culture. But how should we understand his life and his ideas? – ideas that should, it seems to many modern observers, have been far more influential than they actually were.

In this essay I want to introduce you to the John Snow revealed by a generation of medical historians. He is a man, not a marble statue, neither before nor ahead of his time (whatever that might mean), but clearly and intriguingly of it. Snow lived in an age of revolutions, in a time of startling new knowledge and radical uncertainties. …

…from the early nineteenth century European doctors began to move away from a view of disease as a general constitutional imbalance and towards a new focus on specific causes and localised lesions in organs and tissues. But when ‘Asiatic cholera’ began to move west from Bengal in 1817, it was seen at first to be a new and much more severe version of a known condition, one to which victims might be predisposed by their environment, lifestyle and constitution. The great transformation in attitudes towards the disease began with the first European epidemic of 1831-32. It is difficult to exaggerate the fear provoked by cholera’s seemingly inexorable movement across continents and oceans towards Britain. An editorial in the Quarterly Review called it:

        One of the most terrible pestilences which have ever devastated the earth … If this malady should really take root and spread in these islands, it is impossible to calculate the horror even of its probable financial results alone.

How typical of the High Tory Quarterly – ‘so savage and Tartarly’, in Byron’s words – to think first of money. But here, again, we encounter a paradox. In Victorian politics and culture, cholera was enormously significant. As we shall see, it provoked a revolution in public health, political ideology and the treatment of the poor. It became a running theme in the Times, the Lancet, the novels of Charles Dickens, and the scribblings of many less distinguished hacks and pamphleteers. And it gave its name to an age: historians still refer to the middle third of the nineteenth century as ‘the cholera years’.

Demographically, however, cholera’s impact was less clear-cut. It was epidemic, not endemic like tuberculosis, and Britain suffered four short epidemics over four decades (1831-2, 1848-9, 1853-4, and 1866). Compare this with the Black Death, which returned dozens of times over three centuries, and in its first visitation carried off perhaps a third of Europe’s population. Over the nineteenth century cholera killed far fewer people than tuberculosis or the diseases of childhood. Even at the height of the 1831-32 epidemic, cholera was never more than the third most common cause of death, after consumption and convulsions.  So how can we explain the peculiar fear and horror of ‘Asiatic cholera’?

First, think of the name. ‘Asiatic’ or ‘Indian cholera’ reflected the perceived origin of the disease in Bengal, but it also expressed disquiet about the underside of British imperialism. For Britain, the nineteenth century was an age of endless movement, of wars, migrations, exploration and trade. One distinctively Victorian vision of utopia was built on the free movement of people, commodities and capital. For a time, it seemed impossible to have this without a free trade in diseases like cholera. The old, gentle, seasonal cholera became known as cholera nostra, ‘our cholera’; the new ‘Asiatic cholera’ was, so to speak, ‘their cholera’ – a disease of filthy, uncivilised savages, whether they dwelt in the slums of Soho or the bustees of Calcutta, which threatened to overwhelm the civilised heart of imperial government.

And when ‘Asiatic cholera’ did come, it came swiftly and without mercy. Epidemics were intense and seemingly indiscriminate, killing the fit and the strong with the young, the aged and the weak. Victorian culture was peculiarly obsessed with the idea of a ‘good death’, slow, dignified and with time enough to settle one’s affairs and make peace with God. In Christopher Hamlin’s words, cholera ‘liquefied a body as fluids streamed uncontrollably and insensibly from both ends.’ Put more prosaically, victims had roughly a one in two chance of fitting themselves to death in their own watery shit, within a day or even half a day of infection. Contemporary medicine could do nothing beyond the standard general remedies of brandy, opium, bleeding and purging, and many hospitals sensibly, if cynically, refused to admit infectious patients. …

…Nineteenth-century European governments feared revolution on French lines, and cholera brought these fears to a new pitch in an era that also witnessed famines, economic depressions, and the rise of working-class political movements like Chartism. Cholera challenged the power and accountability of a liberal state like Britain, and pointed an accusing finger at the moral squalor of those who (depending upon your political persuasion) let themselves and their families live in filth, or paid their workers so little that they had no choice but to live in filth, or paid their workers so little that they had no choice but to live in filth. In Charles Kingsley’s novel Two Years Ago, published in 1856, one character confesses the meaning of cholera:

        I have been a very dirty, nasty fellow. I have lived contented in evil smells, till I care for them no more than my pig does … I have probably been more or less the cause of half my own illnesses, and of three-fourths of the illnesses of my children.

Fittingly, then, the first revolution cholera sparked was not medical but political. By the early 1830s Britain’s Elizabethan Poor Law was coming apart at the seams. This system relied upon individual parishes to provide for their own poor, but in the new industrial cities the density of population and the sheer numbers of paupers made it unworkable. Its replacement – the 1834 New Poor Law – embodied the spirit of laissez-faire capitalism, and the Malthusian concept of poverty as the result of individual moral failure. Under the principle of ‘less eligibility’, life on poor relief would be worse than the worst available job, providing a rational economic incentive for the poor to find work, even if they had to migrate. The dismal quality of poor relief would be guaranteed by providing it only in workhouses – prison-like institutions where the poor would be kept alive, but on the most meagre rations and in the most humiliating circumstances.

Overseeing the New Poor Law was the Poor Law Board, and overseeing the Board was its secretary, Edwin Chadwick: an ambitious young lawyer, often cited as one inspiration for Charles Dickens’ Gradgrind. Chadwick had been involved in drafting the New Poor Law, but he quickly noticed that in practice it did not seem to be working. Intended to reduce the cost of welfare and the numbers of paupers, its costs were rising rapidly, and the workhouses were almost always full; clearly the poor were not being driven back to work. In 1839 Chadwick received a government commission to investigate the lives of the poor, and in 1842 he published his masterwork – the Report on the Sanitary Condition of the Labouring Population of Great Britain. In this long, desiccated book – a Gradgrindian take on Dickens’ double-decker novels – he set out an entirely new way of thinking about poverty, dirt and disease.…

…It is no coincidence that Snow’s work on cholera took place against the backdrop of London’s liveliest and filthiest district. From its origins as a genteel West End suburb in the seventeenth century, Soho had always been seen as different: foreign, subversive and seductive, embodying London’s confused attitudes towards pleasure and pain, cleanliness and dirt – not only physical filth, but also moral and political pollution. By the mid-nineteenth century Soho was poor and dirty, but industrious; trade directories of the period reveal grocers, bonnet-makers, bakers, tailors, masons, shoemakers, brewers and many other artisan trades jostling for space with nuns, prostitutes, and exiled dissidents like Karl Marx. Space, however, was one thing they could not manufacture, and it was not unusual for Soho’s residents to sleep five or six to a room. And like all Londoners, they faced a pressing problem: how to get rid of their excrement?

For centuries most London houses had cesspits in the basement, which were emptied regularly by the ‘night-soil men’. (Much of this ‘night-soil’ was used to manure the farms and market gardens that grew the city’s food, a gift for satirists who depicted London as a monster feeding on its own excrement.) Through the early nineteenth century water-closets, and the sewers they necessitated, became more popular. When the 1848 Nuisances Removal and Contagious Diseases Prevention Act banned cesspools and required all existing buildings to have sewer connections, the effect was swift and appalling. In the words of Joseph Bazalgette, the man who rebuilt London’s sanitation system in the 1860s and 1870s:

        [W]ithin a period of about six years, thirty thousand cesspools were abolished, and all house and street refuse was turned into the river.

Until the 1820s the Thames had been a comparatively clean river, and a number of private water companies pumped water directly from the river, in its natural – we might say ‘untreated’ – state, into the homes of their customers. By the early 1850s, the river was filled with sewage, churned back and forth by two tides a day. Arthur Hassall provided a pithy summary of this situation:

        According to the present system of London Water Supply, a portion of the inhabitants of the metropolis are made to consume, in one form or another, a portion of their own excrement, and, moreover, to pay for the privilege….

… Within three years Snow himself was dead. On 10th June 1858 he was found unconscious at his desk, having suffered a stroke. He lingered for a week before dying at the age of forty-five. By the time of his death British public health was changing, and the genial diplomat John Simon had replaced the autocratic doctrinaire Edwin Chadwick. Simon pursued a broad-based programme of epidemiological research and sanitary reform, overseeing the reconstruction of London’s sewerage system by Joseph Bazalgette. In his English Sanitary Institutions, published in 1890, long after his retirement, Simon praised Snow’s work as ‘probably … still the most important truth yet acquired by medical science for the prevention of epidemics of cholera’.

In paying this handsome posthumous tribute Simon retrospectively extended his policy of building an inclusive medical and political consensus. Equally, however, he was well aware that Snow’s work had had little influence on the course of British public health in the decades after his death. Medical thought gradually converged around the idea that cholera was ‘a fecal disease caused by a specific agent’, particularly after the last British epidemic in 1866. William Farr became convinced that the disease was water-borne, and a Lancet editorial in the same year proclaimed that:

The researches of Dr Snow are among the most fruitful in modern medicine … We owe to him chiefly the severe induction by which the influence of the poisoning of water-supplies was proved.

But most doctors (including Simon) continued to accept a multi-causal model in which contaminated water was one of many factors, and invisible materies morbi were still a hypothesis. The physician Henry Acland, for example, studied a cholera outbreak in Oxford in 1854, and came to the conclusion that it could be transmitted by water. But Acland also argued that the cholera poison originated in the atmosphere, possibly from electrical discharges during thunderstorms.

Even if Snow’s contemporaries had accepted his conclusions in 1854-55, it is not clear what practical difference this would have made. Without Snow’s influence, a movement to improve London’s water quality was already under way by the mid-1850s, along with a more general effort to clean up the industrial cities. Bazalgette’s immense project, begun in 1858 and completed in 1875, included filtration of drinking water and the complete separation of fresh water and sewage. But this was rooted in Simon’s broad sanitarian consensus, refracted through the concerns of contemporary politics and the mighty capabilities of mid-Victorian civil engineering. It had not been provoked by a revelation that cholera was transmitted by dirty water alone. Indeed, a public health movement concentrating on dirty water might have lacked the wider environmental gaze of Simon’s sanitary reform. In his evidence to a parliamentary committee in 1855 Snow had argued that, since filth diseases were not spread by poisonous vapours, there was no need to restrict ‘noxious trades’ and factory chimneys. And when Robert Koch announced the identification of Vibrio cholera in 1883 – the single most important step in establishing the modern bacteriological view of cholera, though one anticipated by an obscure Florentine doctor, Filipo Pacini, in the 1850s – his paper did not mention Snow. On the Mode of Communication of Cholera had, in Christopher Hamlin’s words, ‘disappeared into the black hole that swallowed cholera publications’.

But Snow never disappeared entirely. His studies were cited, from time to time, in textbooks of public health and epidemiology published in Britain and the US – books like William Sedgwick’s Principles of Sanitary Science, published in 1901. His rediscovery, and the beginning of the process that turned him into the ‘founding father of epidemiology’, is usually dated to 1936, when Wade Hampton Frost, first Professor of Epidemiology at Johns Hopkins, republished the second edition of On the Mode of Communication of Cholera. Frost was motivated not by mere historical curiosity, but by urgent professional concerns. At the time epidemiology was seen as a poor relation of bacteriology. By setting out a ‘useable past’, and by presenting Snow as a heroic founding figure who had used pioneering epidemiological work to end an epidemic, Frost sought to raise the relative status of his discipline, and to make a case for its importance in modern urban life. A subsequent generation of epidemiologists took up Frost’s version of Snow, and this myth-making has continued. Several textbooks published in the US in the 1950s and 1960s, for example, silently altered his map, making it appear closer to the principles of contemporary epidemiology. In giving Snow the recognition we now think he merits, we have, it seems, tried repeatedly to improve on the facts of his life. A desire to promote evidence-based medicine has overshadowed the truths of evidence-based history.

I began this essay with a paradox, and I want to end with one that, to me, seems even more striking – the central paradox of Snow’s life. The more we examine the cultural and political background to the cholera years, the more we grasp the fear and panic, the hatred and division, this disease provoked, the more we can (if we are so minded) appreciate Snow’s courage, dedication and clear, independent thinking. He demonstrated, in ways that retrospectively seem compelling and original, the connection between cholera and contaminated water. In doing so, we may think, he should also have publicly validated new notions of scientific medicine, specific disease causation, and the importance of public health reform rooted in epidemiology, and changed the course of medical history. But he did not.

In one sense, the problem of cholera in the nineteenth century was an epidemiological and pathological puzzle, to be solved – as Snow tried to solve it – with shoe leather, statistics and flashes of clinical insight. But it was also far more than this. The problem of cholera was the problem of free trade and the fate of liberalism. It was the problem of governing industrial capitalism, and living in industrial cities. It was the problem of maintaining imperial control and global military and naval power. It was the problem of the origin and nature of poverty. It was the problem of the proper roles for science and medicine in government and public life. In this larger, political sense, Snow did not solve the problem of cholera. It is ironic, and telling, that many of these problems were solved not by physicians wielding microscopes and germ theories, but by lawyers, administrators and engineers who thought that cholera blew on the wind.

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