Plague, Early History

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Plague, Early History

Introduction

History

Current Issues

Primary Source Connection

BIBLIOGRAPHY

Introduction

Plague has shaped the development of all civilizations. In the recorded histories of Chinese civilization, epidemic disease thrice wiped out one-quarter to over one-third of its population. The Black Death transformed the social, political, and economic landscape of medieval Europe.

Most scientists and historians link bubonic plague in antiquity to rats. Yersina pestis, the bacterium that causes bubonic plague, lives inside the guts of a flea. When inside the flea, Yersina pestis can multiply and blocks the flea's throat area, making the flea quite hungry and in search of new hosts, whether rats or humans. When the flea bites, some of the bacteria is spit out into the bite wound, transmitting the disease.

However, pestilence or plague as recorded in the annals of history does not refer to only one disease. “Plague” did not always describe bubonic plague or the Black Death. Measles, smallpox, flu, dysentery, or typhoid all could have produced a sudden rise in mortality and were referred to in antiquity as plague.

Epidemic disease has likely always been part of human history, but the first written account of its devastating effects originates in the ancient Middle East. The development of horticulture permitted the development of towns, concentrating populations in relatively small areas and facilitating the spread of some diseases. Many historians assert that infectious disease agents spread and thrived because there was a large supply of non-immune, diseasesusceptible people that diseases could attack. People often shared their living quarters with farm animals. Diseases such as cowpox could affect humans or become genetically modified to create epidemics, such as smallpox.

History

Plague in Ancient Egypt, the Middle East, and China

Ancient literature often provides a historical account of ancient epidemics. The Babylonian Epic of Gilgamesh from the seventh-century BC claimed that a visit from the god of pestilence was more preferable than a flooding disaster, and an Egyptian text from 2000 BC compared “fear of Pharaoh with fear of the god of disease in the year of pestilence.” Biblical texts such as the Book of Exodus also report the plagues in Egypt in the form of skin pustules, and the Plague of the Philistines in I Samuel supposedly killed 70,000 in Israel.

In ancient China, references to plague in the Yangtze River Valley were likely endemic malaria or Dengue Fever, a disease common in low-lying areas borne by mosquitoes. The Chinese also were beset by smallpox, and they invented the first techniques of effective prevention in 590 BC called “pock-sowing.” They would grind dried skin scabs from smallpox victims along with musk and apply the mixture to the noses of the healthy. The Chinese also placed matter from the smallpox pustules that arose on the skin into a scratch in the arm of a recipient, in a process called variolation. Exposure to the pathogen usually produced a mild case and gave the recipient immunity, but sometimes a full-blown case would develop. (Effective and safe vaccination for smallpox did not occur until the eighteenth century).

However, another Egyptian text, called the Ebers Papyrus, from 1500 BC does describe an epidemic disease with symptoms similar to the bubonic plague, a bacterial infection that causes buboes, or swelling of the lymph glands. The Ebers Papyrus mentions an illness that “has produced a bubo, and the pus has petrified, the disease has hit.”

Plague in Ancient Greece and Rome

In contrast with Egypt or China where rivers brought irrigation as well as disease-borne vectors, ancient Greece was relatively free of disease. The Greek agriculture did not alter the environment nearly as much as Chinese rice paddies. As a result, the agricultural revolution in Greece did not bring exposure to new diseases.

Threat of epidemics came from the expansion of cities in Greece, increased population density, and exposure to new pathogens from travelers and trade. Ancient Greece was made up of a number of small independent city-states and economics was driven by trade—contact with other peoples brought contact with new diseases. In the fifth century BC, Athens was the most prominent Greek city-state, and it initiated a protracted war with rival city-state Sparta. Expecting to win with its powerful navy, Athens was instead brought to its knees with the appearance of a mysterious epidemic in 430-429 BC that wiped out one-quarter of the Athenian land forces. The ancient Greek historian Thucydides (460–399 BC) in his History of the Peloponnesian War argues the epidemic was the main reason for Athens military defeat—a defining event in subsequent Mediterranean political history.

The identity of this epidemic has been a matter of debate, ranging from scarlet fever to smallpox to bubonic plague to the effects of ergot or a mold on the grain supply. Regardless of the source or causative agent of disease, Athenians had little immunity to it. Because the disease entered the Athenian population with sudden ferocity and then disappeared, several scientists and historians theorize that the pathogen came by sea and soon died out after provoking an accelerated immune response in the local population. The Spartans, more geographically isolated on the Peloponnesian peninsula, were untouched, giving them a decisive military advantage.

Ancient Rome was highly prone to plagues. During the reign of emperor Marcus Aurelius (121–180), the Roman Empire was struck by a destructive epidemic that began in 166 AD and occurred with intermittent frequency until 189 AD. The accounts of the Greek physician Galen (c.130–c.200) about the plague, particularly the incidence of skin rash and gastrointestinal bleeding, have led some scholars to conclude it was probably smallpox. The mortality rate was 7 to 10 percent among the local population, and 10 to 15 percent in the army for a total of five million deaths over the 23-year period. Unlike in China, treatment in the Western World was relatively ineffectual, though it was common knowledge that smallpox survivors were immune to the disease. As early as 430 BC, those who had survived the disease were encouraged to nurse others through the illness, and the Romans also advocated this practice.

The Late Roman Empire and the First Pandemic of the Bubonic Plague

The first pandemic of bubonic plague occurred during the reign of Roman emperor Justinian (483–565). The pandemic probably originated in lower Egypt in 542 and spread via trade routes to Alexandria and then to Constantinople, which served as the capital of the eastern part of the Roman Empire (known as Byzantium) at the time. Forty percent of the population in Constantinople perished. The medical writer Procopius of Caesarea (c.500–c.565) clearly identified the disease as bubonic plague, remarking, “The fever made its attack suddenly. Generally on the first or second day, but in a few instances later, buboes appeared, not only in the groin, but also in the armpits and below the ears.” The plague then continued to Italy, Spain, Britain, Denmark, and ended up in China in 610 AD, and it has been estimated it killed 100 million people, approximately 50% of the human population. As Procopius relates in his History of the Wars, doctors had little recourse or understanding how to treat the disease. They did observe in some patients however that their buboes grew to a large size and ruptured. The patient usually recovered, but tended to have muscle tremors; doctors therefore would lance the buboes in an attempt to increase chances of survival.

WORDS TO KNOW

ENDEMIC: Present in a particular area or among a particular group of people.

ETIOLOGY: The study of the cause or origin of a disease or disorder.

PLAGUE: A contagious disease that spreads rapidly through a population and results in a high rate of death.

QUARANTINE: Quarantine is the practice of separating people who have been exposed to an infectious agent but have not yet developed symptoms from the general population. This can be done voluntarily or involuntarily by the authority of states and the federal Centers for Disease Control and Prevention.

VACCINATION: Vaccination is the inoculation, or use of vaccines, to prevent specific diseases within humans and animals by producing immunity to such diseases. The introduction of weakened or dead viruses or microorganisms into the body to create immunity by the production of specific antibodies.

VARIOLATION: Variolation was the pre-modern practice of deliberately infecting people with smallpox in order to make them immune to a more serious form of the disease. It was dangerous, but did confer immunity on survivors.

Land went uncultivated leading to food shortages, entire villages in rural areas were abandoned, the army shrunk in size, and monastic houses with their close-knit populations were decimated. As the tax base severely declined, civic building projects ceased and public services, including the burial of the dead, virtually disappeared.

Along with these severe cultural effects, the plague in Justinian's reign also greatly affected the history and survival of the Roman Empire. In the West, the Roman Empire had been vulnerable to attacks from Germanic tribes such as the Vandals, Goths, and Ostrogoths, and the western part of the empire had been captured in the fifth century AD. Previous to the outbreak of the disease, Justinian had however made significant inroads in re-taking much of Italy from the Ostrogoths and Northern Africa from the Vandals. The eastern part of the Roman Empire was prospering, silk manufacture in Syria adding to its wealth. Population increased in Greece, Asia Minor, and the Balkans. Justinian had also used his increased revenues to engage in a building program in Constantinople constructing great churches like Hagia Sophia. As Josiah C. Russell remarked in his article “That Earlier Plague,” Justinian's “building program was part of a kind of Golden Age in which literature enjoyed a fine period: Rome still seemed eternal.” In 540, the prospect that the Empire might be restored without straining its resources seemed entirely probable.

However, the devastation of the plague weakened the eastern Roman Empire at a critical juncture. Justinian's army shrunk from 350,000 men to 150,000 on his death in 565. As the plague tended to be especially fatal to young people over ten years of age and pregnant women, the devastation to the population meant that fresh military recruits were increasingly scarce. The offensive in the West was thus abandoned after 565. The resulting power vacuum, along with the birth of Islam, promoted the rise of the Arabic empires in the seventh century.

The Bubonic Plague in Medieval Europe

After the plague epidemics in the sixth and seventh centuries, the disease reappeared sporadically, but did not re-emerge with ferocity until the mid-fourteenth century, erupting in the Gobi Desert in the late 1320s. It is not well understood why the bubonic plague reappeared, but the climate of earth had begun to cool at this time, producing a phenomenon known as the “Little Ice Age,” and this change in environment may have had an effect. We do know that the cooler temperatures resulted in poor harvests and there were famines in Western Europe from 1315–17, which weakened the population and made it vulnerable to epidemic disease. Ultimately, one-third of the population of Western Europe perished, and populations did not return to their previous levels until the sixteenth century. Urban areas like Florence lost between half and three-quarters of their population.

As in the sixth century, the plague followed trade routes in its spread westward, reaching Sicily by 1347, and in late 1347, the Italian mainland, arriving in Germany via Rhine trade routes, and then France and England in 1348 when the plague was at its peak. From reading primary sources, it seems the plague took two forms in the fourteenth century: a septicaemic plague, which attacks the blood, and pneumonic plague, which infects the lungs and is an especially virulent airborne disease.

Medical treatment ranged from the sophisticated to the folkloric. Some theologians opined that it was the result of vengeance of God and nothing could be done, but many of the Italian city-states such as Milan and Venice, took more practical measures and attempted to quarantine sufferers, walling up houses found to have inhabitants with plague. The quarantine, the pest house, and health boards often just crowded the susceptible poor together causing higher mortality, while the urban wealthy fled the city, segregating themselves in the country away from plague sufferers.

Many correctly thought the disease was thought to be transmitted by air, but in an era with no knowledge of microorganisms, it was thought bad smells or miasmas caused infections. Incense and aromatic oils were hawked as cures, as were posies of flowers to be held to the face.

Pope Clement VI (1291–1352) consulted the Parisian medical faculty in 1348 to get their opinion, and they theorized that the disaster was due to astrological events, an unfortunate conjunction of Saturn, Jupiter and Mars that caused hot, moist conditions, which in turn caused the earth to exhale poisonous vapors. Astrology and medicine were intricately intertwined at this time, with the macrocosm of the universe thought to affect the “little world” or microcosm of the body, so their explanation was taken quite seriously. The physicians advised not to eat any food thought to be hot or moist that would add to the effect of the vapors and particularly thought fish were dangerous to include in the diet.

Some expressed their despair at events via religious fanaticism. Groups of flagellants whipped themselves in public to do penance for sins, some believing the end of the world was approaching. Others blamed religious and ethnic minorities such as Jews, Moors, or Roma, accusing them of poisoning town wells and causing the disease. There were pogroms, or mass-killings, of Jews and Roma in the fourteenth and fifteenth centuries. In Strasbourg in 1349, nearly 200 Jews were burned to death. In response to this persecution, some of the Jewish population moved into Eastern Europe into areas of Poland and Lithuania.

The massive population loss also had great economic effects. Labor shortages meant that wages rose, and landlords attempted, often forcefully, to hold on to the serfs they had and to enforce more labor duties. It is little surprise that in the 1380s there were a number of peasant revolts (the Jacquerie in 1358, the Peasants’ Revolt in England in 1381, and the Catalonian Rebellion in 1395) as laborers asserted their rights in a market that should have been favorable to them.

Landlords shifted production on the land from foodstuffs, the demand for which was declining with a smaller population, to pastoral agriculture (sheep and cattle raising). Grazing cattle or sheep required less farm labor. Women also found their labor in demand. The two centuries after the plague have been described as an “early golden age for women” as several female guild masters and business owners appeared. Marriage rates also decreased after the bubonic plague. The disease seemed to disproportionately kill young men, so many women married late or not at all, and thus turned to convents or cottage businesses to earn their livings.

These disruptions and changes to the social and economic fabric of medieval society have caused many historians to claim that the plague was the dividing line between the Middle Ages and the Renaissance. Certainly it seems that more secular values that became more important in the Renaissance, as opposed to the spiritual values of the medieval era, began to dominate society. For a variety of political reasons, the popes during the plague also did not live in the spiritual home of Rome and the Vatican, but in southern France in Avignon to the scandal of many. The Crusades in the 1290s had also been resolute failures and the Holy Lands were lost.

IN CONTEXT: CULTURAL IMPACTS

1n 1687, English physicist Sir Isaac Newton (1642–1727) published a law of universal gravitation in his important and profoundly influential work Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy). Newton articulated a law of universal gravitation that states that bodies with mass attract each other with a force that varies directly as the product of their masses and inversely as the square of the distance between them. This mathematically elegant law, along with Newton's laws of motion, became the guiding models for the future development of physical law.

Born in Woolsthorpe, Lincolnshire, England, Newton did not initially distinguish himself in school, and he was removed by his mother in the late 1650s to work on the family farm, but Newton proved a worse farmer than scholar. His uncle, however, encouraged the boy to go to Cambridge in 1660. Five years later Newton graduated, even though he had failed a scholarship exam in 1663 due to his lack of knowledge concerning geometry.

Newton returned to the farm in 1665 to escape the bubonic plague, which at the time was decimating London. In his year of enforced isolation, his annus mirabilis or miracle year, he invented the calculus, discovered the color spectrum of light, and derived his law of universal gravitation.

Accompanied by the disaster of the plague, the loss of faith in the church may have set the stage for Renaissance secularism. The Catholic Church seemed unable to offer the degree of spiritual comfort required in an era of great loss, and many adopted the “live for today” attitude, enjoying life while they could in uncertain times. For instance, the Italian author Giovanni Boccaccio's (1313–1375) Decameron, written shortly after the plague, is a literary masterpiece which has as it premise a group of lords and ladies who escaped Florence to the country town of Fiesole during the epidemic. While in exile they told stories to amuse themselves and pass the time, often displaying themes of lust, love, and a decidedly commercial, urban, and secular ethic.

The bubonic plague, though it never reoccurred in as virulent a manner as in 1348, did return several times in the fifteenth century, and there were local epidemics until the mid-seventeenth century. The last occurrence of the bubonic plague in Western Europe was in 1665 in London just before the Great Fire burned the medieval wooden houses and seemingly cleansed the capital of fleas and rats responsible for the disease.

In 1665, a young man called Isaac Newton (1642– 1727) fled the plague raging in Cambridge to his parent's home in Woolsthorpe, Lincolnshire. In his year of enforced isolation, his annus mirabilis or miracle year, he invented the calculus, discovered the color spectrum of light, and derived his law of universal gravitation.

Current Issues

Another great pandemic of plague spread through China, southeast Asia, and India beginning in 1855. The advent of the railway and increased migration helped the disease spread rapidly in Asia, India, and parts of Russia. Over the following 50 years, plague (predominantly pneumonic) spread to every inhabited continent. The so-called Third Pandemic killed 12 million people, primarily in Manchuria and Mongolia.

Several scientists have theorized that the Second Pandemic, the Black Death, may not have involved bubonic plague, but another form of plague that is not present today. Others assert that the Black Death was too virulent to have been bubonic plague, suggesting that a highly contagious hemorrhagic fever—akin to modern Ebola or Marburg—was the epidemic disease of the medieval plague. The theories are controversial and Yersina pestis remains the predominantly accepted culprit of the Black Death.

While researchers have been scouring written sources for years for clues about ancient plagues, they had been limited to matching described symptoms to known disease behaviors. Archaeological and forensic research may aid the identification of past epidemics. Eva Panagiotakopulu, an archaeologist from the University of Sheffield, theorizes that Egypt was the very source of the deadly bubonic plague, which has been commonly thought by historians to have its origins from the Near East. Panagiotakopulu found fossilized fleas in ancient Egyptian's habitations, as well as remains of Nile rats that could have carried the disease. She speculates that the Nile River Valley was a natural habitat for flea-carrying rats and that endemic flooding drove large rat populations into urban areas.

Primary Source Connection

Often, key components of research published in scientific journals are written in accessible language. Journal articles usually follow a structured form, with an abstract or overview followed by supporting data and arguments, and end with a summary. The abstract, at the top of the article, introduces the reader to the key components of the research using as broad and easily understandable terms as possible. The methods and body of the research and evidence follow, and in the conclusions, much of the abstract is restated as it relates to the evidence presented. By reading the abstract and conclusions of scientific literature, the reader can often gain a basic picture of the research. Although the body of the article can contain arguments and data that are designed for scientists, the abstract and summary or conclusion sections often contain valuable and readable information for nonscientists.

In this extract from the journal Emerging Infectious Diseases, the author Michel Drancourt presents his evidence that Yersinia pestis was the cause of at least two historical pandemic plagues using the classic form for reporting in scientific journals. Michel Drancourt is professor of medical microbiology in Unité des Rickettsies, Marseille Medical School, Marseille, France. His research interests are paleomicrobiology of plague and bartonelloses.

Yersinia pestis Orientalis in Remains of Ancient Plague Patients

Abstract

Yersinia pestis DNA was recently detected in human remains from 2 ancient plague pandemics in France and Germany. We have now sequenced Y. pestis glpD gene in such remains, showing a 93-bp deletion specific for biotype Orientalis. These data show that only Orientalis type caused the 3 plague pandemics.

Three historical pandemics have been attributed to plague. The causative agent, Yersinia pestis, was discovered at the beginning of the ongoing third pandemic. The etiology [origin or cause] of the 5th–7th-century first pandemic and the 14th–18th-century second pandemic, however, remained putative until recently….

THE STUDY

We had historical evidence that 3 mass graves excavated in France were used to bury bubonic plague victims. In Vienne, 12 skeletons, including 5 children, buried within the ruins of a Roman temple have been dated from the 7th–9th centuries both by a 5th-century coin and 14C dating. In Martigues, 205 skeletons buried in 5 trenches were dated from 1720 to 1721 on the basis of coins and detailed parish bills that listed the victims. In Marseille, 216 skeletons buried in a huge pit dated from a May 1722 epidemic relapse. We previously confirmed the diagnosis of plague at this site. Eighteen teeth from 5 skeletons in Vienne, 13 teeth from 5 skeletons in Martigues, and 5 teeth from 3 skeletons in Marseille were processed for the search for Y. pestis DNA in the dental pulp. The teeth were processed according to published criteria for authenticating molecular data in paleomicrobiology: 1) there should be no positive control; 2) negative controls, as similar as possible to the ancient specimens, should test negative; 3) a new primer sequence targeting a genome region not previously amplified in the laboratory should be used (suicide PCR); 4) any amplicon should be sequenced; 5) a second amplified and sequenced target should confirm any positive result; and 6) an original sequence that differs from modern homologs should be obtained to exclude contamination.

IN CONTEXT: CULTURAL CONNECTIONS

Plague created panic and desperation in the pre-modern world and those fears lingered in the social psyche—often manifesting themselves in bizarre form.

Mistakes in pronouncement of death—and premature burial— are now highly unlikely in the industrialized world, but until the twentieth century there were less definitive means of determining death. As a result, it was not unheard of for a person ill with plague to fall into a coma or a stupor and to appear to observers to be dead when, in fact, the patient was still alive. Plague often led to fears of premature burial.

Bodies were often quickly buried, particularly in times of plague or cholera. There have been numerous tales, dating back to very early history, of the apparently dead spontaneously reviving and living on for extended periods of time. One such story is that of Marjorie Halcrow Erskine of Chirnside, Scotland. She was reported to have died in 1674 and was buried in a rather shallow grave by the village sexton, who planned to rob her grave and steal her jewelry. As the sexton attempted to cut off the woman's finger in order to obtain one of her rings, she suddenly revived. Ms. Erskine was able to return home, and she lived a full life, giving birth to and raising two sons.

In the seventeenth through nineteenth centuries, in times of plague, cholera, and smallpox epidemics, a substantial number of premature burials were reported. A nineteenth century researcher named William Tebb published a book in 1896 titled Premature Burial and How It May Be Prevented. In it, he detailed 219 instances of near premature burial, 149 cases of genuine premature burial, ten cases of dissection before actual death, and two cases in which embalming began before death had occurred.

During the eighteenth and nineteenth centuries, various methods were employed to ensure that an individual was, in fact, dead. In one method, a hot poker was applied to the deceased patient, while another involved pouring liquid into the patient's mouth. Yet another creative strategy required the attending physician to stick the finger of the apparently deceased into his (the physician's) ear in an effort to feel the buzz or hum of life. In 1846, a French physician named Eugene Bouchut suggested that the stethoscope be used to determine when the heart stopped beating in order to determine that death had occurred.

The most extreme measures for preventing premature burial occurred in Germany between 1790 and 1860. There, roughly fifty centers called Leichenhäuser, or waiting mortuaries, were built. In these buildings, corpses were kept in warm rooms. Each corpse had strings wrapped around fingers and toes, with the other ends of the strings attached to bells. The bells were meant to be rung by the awakening person, but there is no report of a bell ever ringing. The bodies were maintained until evidence of putrefaction was unequivocally present (complete with requisite stench). Some of the waiting mortuaries had luxury and common rooms—some were even open for public observation. A later Leichenhaus in Vienna utilized an electronic bell system.

Individuals went to elaborate lengths to prevent premature burial. Some requested that their heads be severed. Others wanted their arteries slashed (Danish writer Hans Christian Anderson, 1805– 1875), their bodies dissected (Polish composer Fré déric Chopin, 1810–1849), or their bodies embalmed. All these measures were designed to ensure with absolute certainty that the individual was dead before he or she was buried.

In 1896, Count Karnice-Kamicki, a chamberlain to the Russian tsar, invented a device to be affixed to a coffin in order to avoid premature burial—or, rather, to provide a means of correcting that unfortunate situation. His mechanism was comprised of a tube running from the inside of the coffin to an airtight box several feet above the ground. A spring, which ran the length of the tube, was attached to a glass sphere sitting on the chest of the body. The slightest movement of the body would trigger the spring, causing the lid of the airtight box to pop open, thus allowing light and air into the interior of the coffin via the connecting tube. The box above the grave also contained a flag, a bell or a buzzer, and a light that could be seen and heard from a considerable distance.

Accordingly, DNA samples were submitted for suicidenested PCR conducted by using 1 negative control (18th-century teeth from skeletons of persons without anthropologic and macroscopic evidence of infection) for every 3 specimens…. The sequences were compared in the GenBank database (www.ncbi.nlm.nih.gov/GenBank) using the multisequence alignment Clustal within the BISANCE environment.

Conclusions

In this study, contamination of the ancient specimens is unlikely because of the extensive precautions we took, including use of the suicide PCR protocol excluding positive controls. Accordingly, glpD gene had never been investigated in our laboratory before this study, and negative controls remained negative. The specificity of the amplicons was ensured by complete similarity of experimental sequences with that of the Y. pestis Orientalis glpD gene. One site (Marseille, 1722) was previously positive for Y. pestis after sequencing of 2 different targets (chromosome-borne rpob and plasmid-borne pla genes) in other specimens collected in other persons's remains.

These results therefore confirm the detection of Y. pestis-specific DNA in plague patients’ remains from the first and second epidemics. We observed a 93-bp inframe deletion within the glpD gene sequences obtained from ancient dental pulp specimens. This deletion has been found only in Orientalis biotype isolates in 2 independent studies comprising a total of 77 and 260 Y. pestis isolates, respectively, of the 4 biotypes.

After previous demonstration of Y. pestis Orientalistype multiple spacer type sequences in Justinian and medieval specimens, we now have cumulative evidence using 2 different molecular approaches that Y. pestis closely related to the Orientalis biotype was responsible for the 3 historical plague pandemics.

Michel Drancourt

DRANCOURT, M, ET AL. “ YERSINIA PESTIS ORIENTALIS IN REMAINS OF ANCIENT PLAGUE PATIENTS.” EMERGING INFECTIOUS DISEASES. (FEBRUARY 2007): AVAILABLE AT <HTTP://WWW.CDC.GOV/EID/CONTENT/13/2/332.HTM> (ACCESSED MAY 28, 2007).

BIBLIOGRAPHY

Books

Boccaccio, Giovanni. The Decameron. Mark Musa, trans. New York: Signet, 1992.

Bollet, Alfred J. Plagues and Poxes: The Impact of Human History on Epidemic Disease. New York: Demos Medical Publishing, 2004.

Carmichael, Anne G. Plague and the Poor in Renaissance Florence. Cambridge: Cambridge University Press, 1986.

McNeill, William Hardy. Plagues and Peoples. New York: Doubleday, 1998.

Procopius, History of the Wars. H. B. Dewing, trans. Cambridge, Mass.: Harvard University Press, 1914, Vol. I, pp. 451–473.

Wrigley, E.A., and R.S. Scofield. The Population History of England, 1541–1871: A Reconstruction. Cambridge, Mass: Harvard University Press, 1984.

Periodicals

Gross, C.P., and K.A. Sepkowitz. “The myth of the medical breakthrough: smallpox, vaccination, and Jenner reconsidered.” International Journal of Infectious Disease 3 (1998), pp.54–60.

Littman, R.J., and M.L. Littman. “Galen and the Antonine Plague.” The American Journal of Philology 94, 3 (Autumn 1973), pp. 243–255.

Morgan, Thomas E. “Plague or Poetry? Thucydides on the Epidemic at Athens.” Transactions of the American Philological Association 124 (1994), pp. 197–209.

Russell, Josiah C. “That Earlier Plague.” Demography 5, 1 (1968), pp. 174–184.

Web Sites

Walker, Cameron. “Bubonic Plague Traced to Ancient Egypt.” National Geographic News. March 10, 2004. <http://news.nationalgeographic.com/news/2004/03/0310_040310_blackdeath.html> (accessed May 17, 2007).

Anna Marie E. Roos