Disease is understood to be a deviation from the norms that define health in any specific culture. Diseases may be noncommunicable, originating in genetic or environmental factors, or they may be communicable, or infectious, caused by a microorganism that can be transmitted from person to person. Diseases may affect individuals in small numbers, or they may affect large proportions of a population. When substantial numbers of cases are involved, and when these numbers vary significantly over time, the outbreak is called an epidemic. An epidemic affecting a very large area is a pandemic, and one that is consistently present in the population is endemic. Although HIV/AIDS is typically called an epidemic, it is also by now pandemic, in that its reach is worldwide, and it appears to have become endemic among certain populations. Thus, usages of these terms to describe the spread of HIV/AIDS vary.
Epidemics, which have existed throughout history, attract attention and cause alarm because of their scope and destructiveness but also because they come and go, often unpredictably. Even today, an outbreak of Ebola hemorrhagic fever, which may result in several dozen deaths, generates far more attention than malaria, which remains endemic in many parts of the world and kills hundreds of thousands of people a year. In the past, when the causes of disease were poorly understood, epidemics frequently caused enormous alarm and were often blamed on unpopular social groups or even on the sufferers themselves.
Although medical science has advanced tremendously in its understanding of disease, particularly in the nineteenth and twentieth centuries with the development of germ theory and the use of antibiotic drugs, the social response has changed far less over time. Studying epidemics of the past can, therefore, illuminate social, governmental, and even medical responses to more recent diseases, including AIDS.
Disease depends on relationships. Without both hosts and vectors, or organisms that complete the chain of transmission, microorganisms would not be able to reproduce and cause disease; without sizable host populations, diseases would die out quickly. Infectious disease is, therefore, a function of civilization. Until recently in most societies, epidemics were common and frequently devastating. Some of these have left lasting impressions, either because of their destructive force or because of the ways in which they have been understood.
The two most memorable diseases of the Middle Ages were plague and leprosy, one a rapid killer of millions, the other very slow but equally horrifying because of the ways in which it was regarded and understood. Plague is caused by a bacillus (Yersinia pestis) that is transmitted by fleas which commonly infest rats and other rodents; its most frequent symptoms include fever, severe headaches, delirium, prostration, and buboes, which are painful, extreme enlargements of the lymph nodes of the groin and armpits. Death commonly occurs within eight days of infection.
The most famous episode of plague in Europe, the Black Death, seems to have originated in Central Asia; it arrived in Milan in 1348, carried by shipborne rats. By 1351, all of the European world was affected. In some areas, two-thirds to three-quarters of the population died, perhaps as many as 25 million overall. This mortality caused tremendous social disruption: the Italian author Giovanni Boccaccio wrote that "brother forsook brother, uncle nephew and sister brother and oftentimes wife husband; nay (what is yet more extraordinary and well nigh incredible) fathers and mothers refused to visit or tend their very children, as [if] they had not been theirs."
Among the many unfounded theories of origin was one that held that Jews had poisoned the wells; in Basel, Switzerland, city officials carried out the citizens' desires for retribution by enclosing the city's entire Jewish community in a wooden building and burning them to death. The plague ultimately subsided when the flea-carrying rats were displaced by another species of rat that was less habitable to the plague-bearing fleas.
Though far less contagious than plague, leprosy has also left deep and painful impressions on historical memory. Caused by Mycobacterium leprae, this disease destroys nerve endings, blood vessels, ligaments, skin tissue, and even bone and can cause marked deformations of the extremities, face, and voice. These deformations often horrify others; consequently, societies have frequently associated leprosy with sin and have expelled its sufferers from their midst.
The biblical book of Leviticus, for example, commands that the leper must cry, "'Unclean, unclean,'" and ordains, "He shall dwell alone; without the camp shall his habitation be." Medieval Christianity, too, excluded the leper from society, viewing him or her as a person dead to the world. One eighth-century medieval ritual required the leper to stand in an open grave while a priest announced, "I forbid you ever to enter the church or monastery, fair, mill, market-place, or company of persons ... ever to leave your house without your leper's costume ... ever to touch children or give them anything." This living death was sometimes moderated by the promise of speedy redemption in the afterlife, but the association of leprosy and sin remains a powerful and disturbing one.
Mass destruction and social condemnation also characterized two epidemics of the Renaissance, smallpox and syphilis, diseases that may well have sprung into prominence as a direct result of the explorations of the age. Smallpox had existed in Asia, and then in Europe, for centuries but was apparently unknown in the Americas until Europeans arrived there in the fifteenth century. There the disease caused colossal mortality, with as much as half the population dying. It has been argued that smallpox, far more than the military skills of the colonizers, was responsible for the European conquest of the Americas.
Meanwhile, syphilis was first recorded in Europe in 1493, which was, perhaps coincidentally, immediately after Christopher Columbus and his sailors returned to Spain. Far more virulent a disease than it is today, syphilis spread furiously through Europe. Meanwhile, every nation tried to categorize it as a disease brought from outside, by foreigners, with the Russians calling it Polish, the Poles ascribing it to Germans, and the Germans, English, and Italians calling it the "French sickness." The Dutch and Portuguese ascribed it to the Spanish, while the Japanese blamed the Portuguese.
The process of assigning blame for syphilis was accompanied by severe moral condemnation. Syphilis was obviously transmitted by sex, and so many, like the bishop and physician Gaspare Torella, questioned whether its sufferers even deserved a cure: "Ought one to work against the will of God, who has punished them by the very means in which they had sinned?" Syphilis, other venereal diseases, and AIDS have often incurred such judgments because of the supposedly voluntary and sinful ways in which they are passed from one person to another.
Memorable epidemics in the following centuries included the European smallpox pandemic of 1614, outbreaks of plague in London in 1665 and Marseilles in 1720, and an epidemic of yellow fever in the new American capital, Philadelphia, in 1793. These, too, were often seen as punishment for sin; one seventeenth-century English writer described the plague as "a broom in the hands of the Almighty with which he sweepeth the most nasty and uncomely corners of the universe."
The nineteenth century was marked by four pandemics of cholera, one of which started in 1826 in India and had spread by 1832 to Russia, Persia (Iran), Continental Europe, Great Britain, and North America. Cholera, which can kill within a day, is caused by fecal contamination of food and water; it brings on severe cramps, vomiting, fever, dehydration, and sudden death. Because cholera often afflicted the overcrowded and malnourished poor, the New York Times in 1866 called it "the curse of the dirty, the intemperate, and the degraded."
Similar views of the relationship between social conditions and disease characterized the construction of tuberculosis (TB), the nineteenth century's most devastating chronic disease. TB is typically a chronic disease whose symptoms include fatigue, weight loss, chills, aches, fevers, and a characteristic violent cough that sometimes brings up bloody sputum. It most commonly affects people, such as the urban poor, whose nutrition is inadequate and who live and work in crowded conditions. By the eighteenth century, physicians and the lay public believed that climate and "dissolute and immoral" living made people susceptible to the disease. Tubercular patients were often urged to take up physically active lives in areas with salubrious weather. Rest cures in sanatoriums were common, and treatment often varied according to the gender and class of the sufferer. Only when Robert Koch discovered in 1882 that TB is caused by a bacterium did the stereotypes that its sufferers were inherently weak or tainted begin to fade away.
The early twentieth century was marked by epidemics such as those of influenza and poliomyelitis, or polio. The great influenza pandemic of 1918 began when the "Spanish flu" struck Chungking in July, Persia in early August, and France two weeks later; in two months it had covered the entire globe, taking 500,000 lives in the United States, 12,000,000 in India, and 22,000,000 overall -- nearly twice as many as World War I. Polio, though far less widespread, caused tremendous fear because it primarily affected children, causing their paralysis and even death. During the early 1950s, the United States experienced an average of 40,000 cases per year. The Salk and Sabin vaccines caused a dramatic drop in these figures, but their use in developing countries, particularly in Africa and India, remains sporadic.
Until recently, at least in the industrialized nations, the 1918 influenza pandemic and infectious disease in general were viewed as parts of a natural history that had more or less come to an end. The remarkable success of vaccines, with smallpox being officially eradicated in 1979, and of antibiotics led to a period from the 1950s to the 1970s during which it seemed that Western medicine could and had introduced an age in which the only remaining threats to health were chronic diseases like cancer. This view was reinforced in 1976 when a recurrence of the 1918 influenza failed to materialize as expected. Antibiosis -- the use of substances produced by one type of microorganism to counteract the effects of another -- caused a revolution in drug therapy in the 1940s. Antibiotics were found to be effective with a broad range of bacterial diseases, including pneumonia, TB, meningitis, diphtheria, syphilis, gonorrhea, and plague. Their effectiveness, however, is increasingly limited by the growth of drug-resistant pathogenic strains.
The advent of AIDS made it clear that hopes for a world free of infectious disease were tragically erroneous, but in fact, proof of this error had been visible around the world to those who were willing to look for it. Cholera alone was epidemic in Asia in the 1960s and in the Middle East, Africa, and the Soviet Union in the 1970s; plague struck India in 1995; other diseases, such as malaria and TB, escaped eradication and have re-turned in drug-resistant forms to pose serious threats to world health. In addition, a variety of new infectious diseases have been reported, many of them rapid, highly contagious, and ferociously destructive of the human body, such as Marburg disease (1967), Lassa fever (1969), Ebola hemorrhagic fever (1976), and, of course, AIDS. Susan Sontag describes the future as "not 'Apocalypse Now' but 'Apocalypse From Now On.'"
In the face of these dangers, it is essential that all aspects of infectious disease be addressed: pathogenic agents, social and environmental contexts, and individual behavior. Each has a part to play, but without attention to all three, a response can rarely be completely effective. To assume that any disease, whether leprosy, cholera, or AIDS, is evidence of the sufferer's moral failings is a destructive belief that adversely affects medical, social, and individual responses. AIDS is neither accidental nor unique but rather one of many diseases that are a permanent part of human existence. In responding to the current pandemic, humanity has the ability both to learn from the past and to provide models -- good and bad -- for the future.
Related Entries:Discrimination; Forecasting; Geography; HIV, Origins of; Seroprevalence; Sexually Transmitted Diseases; Stigma; Tuberculosis
Key Words:epidemic, infectious disease, pandemic, plague, public health, syphilis, [specific epidemic by name]
Further ReadingBrandt, Allan M., No Magic Bullet: A Social History of Venereal Disease in the United States Since 1880, New York: Oxford University Press, 1987
Fee, Elizabeth, and Daniel M. Fox, eds., AIDS: The Burdens of History, Berkeley: University of California Press, 1988
Garrett, Laurie, The Coming Plague: Newly Emerging Diseases in a World Out of Balance, New York: Farrar, Straus, Giroux, 1994
Kiple, Kenneth F., ed., The Cambridge World History of Human Disease, Cambridge: Cambridge University Press, 1993
McNeill, William T., Plagues and Peoples, Garden City, New York: Doubleday, 1976
Morris, R. J., Cholera 1832: The Social Response to an Epidemic, New York: Holmes and Meier, 1976
Quétel, Claude, History of Syphilis, translated by Judith Braddock and Brian Pike, Baltimore, Maryland: Johns Hopkins University Press, 1990
Sontag, Susan, Illness as Metaphor and AIDS and Its Metaphors, New York: Doubleday, 1989
Encyclopedia of AIDS $25 US/832 pp/Illustrated
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Encyclopedia of AIDS $25 US/832 pp/Illustrated
For more about this book, or to order, click here.
It is a part of the publication The Encyclopedia of AIDS.