Pox Americana: The Great Smallpox Epidemic of 1775-82

Germ Colonies

A few months ago, who anticipated that anthrax would be spread by terrorists through the mail? And now there are worries about the return of smallpox, once the most feared disease on the planet. Smallpox has been deemed to have been eradicated, but strains of it still lurk in laboratories with widely varying degrees of security and intent. Our grim new possibilities lend urgency to knowing more about smallpox's dreadful past. History can always help -- if not practically, then intellectually, so that we might better understand the dangers that we may face. Fortunately (if that is the right word), we have a talented and judicious guide in Elizabeth Fenn, who has produced a morbidly compelling account of the great smallpox epidemic that ravaged North America between 1775 and 1782.

Inspired in part by the public awareness generated by AIDS, historians recently began to pay closer attention to the power of past epidemics to shatter and to reshape human societies. A century ago, American historians thought of their continent as once a "virgin land," a vast wilderness virtually untouched by humans until it was colonized by Europeans. The great nationalist historian of the nineteenth century George Bancroft insisted that in 1492 the future United States was "an unproductive waste ... its only inhabitants a few scattered tribes of feeble barbarians." That view obscured the large Indian populations that greeted the first European explorers -- populations soon decimated by the deadly new diseases introduced by the colonizers. Correcting the old view, colonial historians now see North America as, in the words of the late Francis Jennings, a "widowed land" rendered so by the fatal microbes that accompanied the European invaders.

Almost everywhere, the first European explorers and colonists reported horrifying and apparently unprecedented epidemics among the native peoples. During the 1580s, Thomas Harriot described the fate of the Indians near the new English colony at Roanoke Island (in present-day North Carolina):

[They] began to die very fast, and many in [a] short space; in some townes about twentie, in some fourtie, in some sixtie, & in one sixe score, which in trueth was very manie in respect to their numbers....The disease also was so strange that they neither knew what it was, nor how to cure it; the like by report of the oldest men in the countrey never happened before, time out of mind.

In 1633 a New England colonist reported that "it pleased God to visite these Indeans with a great sickness, and such a mortalitie that, of 1000, above 900 and a halfe of them dyed, and many of them did rott above ground for want of buriall."

After 1492, the Indians paid dearly for their former isolation from the larger and more virulent disease pool of Africa, Asia, and Europe. The world's champion killers -- including smallpox, typhus, diphtheria, bubonic plague, malaria, yellow fever, and cholera -- developed in the Old World after the Indians had emigrated to the Americas (approximately 15,000 years ago). From many generations of internal combat with these microscopic invaders, Africans, Asians, and Europeans developed partial defenses: antibodies and immunoglobins. Over time, Europeans and their micro-predators tended to work out a rough and always provisional equilibrium. Most people survived their bouts with disease, enabling human reproduction to keep pace with mortality. Consequently, as colonizers the disease-toughened Europeans carried viruses of even greater danger to others than to themselves. Their breath, blood, sweat, and lice conveyed micro-predators that consumed Indians, who lacked the immunological resistance of past experience.

Smallpox was the most terrifying and most devastating of the diseases that were unwittingly introduced by the colonizers. A highly communicable virus, Variola major passes by the exhalation of victims through the air on moisture droplets or dust particles to enter the lungs of a new host. After an incubation period of twelve days, victims come down with a high fever and vomiting, followed three to four days later by gruesome sores over their entire bodies. Painful, incapacitating, and disfiguring, smallpox transforms people into hideous masses of pustulated flesh. In New England during the 1630s, a colonist described Indians with pustules "breaking and mattering and running one into another.... And then, being very sore, what with cold and other distempers, they die like rotten sheep."

Among Europeans and Africans in the early modern era, the fatality rate usually approximated one-quarter to one-third of the afflicted. Infected Indians died at about twice that rate. Although scarred with pocks and sometimes blinded, the survivors reaped a precious lifetime immunity to the disease. But they could not pass this complete immunity on to their progeny, so every North American generation accumulated the human fuel to feed a spectacular new epidemic.

Compared to the Indians, the British colonists got off lightly. In addition to their better resistance, the colonists benefited a bit from two more systematic measures that restricted the disease: quarantines and an early form of inoculation known as "variolation." Enforced by town or city governments, quarantines confined suspected carriers to remote pesthouses for care by doctors and nurses with the immunity of previous exposure, and for isolation from the rest of the community. During the early eighteenth century, the British and their colonists also began to practice variolation: the intentional implantation of live smallpox matter into an incision made in an arm or a hand. For reasons that are still unclear, smallpox artificially taken through a cut proved less debilitating and less deadly than when contracted randomly and naturally through the lungs. Fewer than five percent of the variolated died, compared to the twenty-five percent ordinarily killed by natural exposure. And as with any bout with smallpox, variolation gave immunity to its survivors.

But both quarantine and variolation measures had problems. In an age of expanding maritime commerce, identifying and confining carriers overtaxed the minimal governments of eighteenth-century America. And even if they were effective in the short term, quarantines imparted no immunity to the local people, leaving them vulnerable to the next diseased newcomer. Variolation was also risky: some patients died, and all of them increased the dangers of exposure for their neighbors who were not taking the treatment. By its considerable expense, variolation benefited the prosperous, who could afford it, while threatening their poorer neighbors, who could not. In self-defense, rather than out of backward prejudice, mobs of common people often drove from their towns any doctors who introduced variolation. To preserve social harmony, some colonies, especially in New England, banned the practice, preferring quarantine as an alternative.

Especially deadly and specialized, Variola suffers from its own success. The disease either kills or affords immunity, rendering victims unsuitable for the virus to linger in or to return to. Elizabeth Fenn observes that "for the parasite this presents a problem. Variola consumes its human hosts as a fire consumes its fuel, leaving spent bodies, dead or immune, behind it." Possessing no carriers or victims other than humans, the virus needs to find new hosts quickly. It thrived in places crowded with people, and benefited from diseased (but not yet symptomatic) travelers visiting new and unaffected communities. Moreover, Variola was deadliest where social chaos prevailed. Bad enough in the best of circumstances, smallpox fatality soared when people lacked nurturing care. Indians died in especially large numbers because almost everyone in a village became sick at the same time, leaving too few to provide food, water, firewood, and care to the afflicted. Malnourished, dehydrated, cold, and demoralized groups rarely survived the virus.

War maximized the crowding, the movement, and the disruption that promoted smallpox. Wars cluster people in filthy military cantonments and refugee camps, and send soldiers marching and civilians fleeing over long distances, and rupture communities with death and fire. Brother-horsemen of the apocalypse, war and pestilence have long collaborated in their deadly work. It was no accident that smallpox came into North America with the invading and rampaging Spanish conquistadors of the sixteenth century. Variola surged anew in proportion to the scale of every subsequent colonial war. As the most extensive and destructive conflict of the eighteenth century in North America, the War of the American Revolution stimulated the most far-ranging and deadly smallpox epidemic since the brutal era of the conquistadors. In addition to Indians, the Revolutionary epidemic killed thousands of Americans of European or African descent, illuminating their shared contacts in misery.

By examining the massive smallpox epidemic that accompanied the American Revolution between 1775 and 1782, Elizabeth Fenn provides a dazzling new perspective that embraces an entire continent. We tend to think of eighteenth-century North America as a group of distinct and isolated regions -- a mismatched set of Spanish, French, Dutch, British, and even Russian colonies. Clustered along distant coasts, these colonies have seemed isolated by a broad and vague interior then still possessed by diverse Indian peoples. Consequently, historians of the American Revolution rarely examine cultures and places beyond the thirteen new states along the Atlantic seaboard. By tracking an epidemic across colonial boundaries throughout North America, Fenn recovers the larger picture that we have long missed.

Like a marker in the bloodstream, smallpox generated far-flung documents, exposing the networks of human contact and exchange that crisscrossed the continent from Quebec to New Orleans, from Mexico City to Hudson Bay, from South Carolina to the Pacific Northwest. The spreading epidemic demonstrated that war and trade had already interlocked the lives and the fates of native and colonial peoples. Fenn overrides the confining and parochial boundaries of regional and national histories to reveal a North American continent surprisingly integrated by colonial war and long-distance trade. In recent years, some scholars have called for a more trans-national approach to American history; Fenn demonstrates how it can be done, and the benefits of doing so.

On the East Coast at the start of the war, the rival British and American commanders had to decide how best to protect their troops from smallpox. The British rather easily opted for variolation. Since the disease was more endemic to the more urbanized mother country than to the predominantly rural colonies (where it came in infrequent but spectacular epidemics), most of the British troops had suffered from and survived smallpox as children or adolescents. The few who needed variolation could be easily cared for and protected by the majority. The superior professionalism, organization, and discipline of the British regulars also rendered effective their quarantine while they were undergoing the treatment.

George Washington faced a much tougher call. Most of his troops were American by birth and lacked the immunities of past exposure. Variolating them all was an expensive and massive operation initially beyond the limited funds, the makeshift organization, and the faulty discipline of the new rebel army. To variolate part of the army would increase the exposure for the rest, and to inoculate the whole would render them defenseless against British attack for several weeks. Consequently, Washington and his subordinate officers initially rejected variolation in favor of quarantine -- which proved ineffective among raw troops who believed that fighting for liberty meant obeying only the orders they liked.

Sensitive to their greater vulnerability to smallpox on an epidemic scale, the Americans suspected that the British practiced a crude form of biological warfare by sending infected civilians and clothing within the American lines. Although useful as anti-British propaganda, such reports also produced panic in American ranks. Fenn tends to credit these rumors, although in only one surviving document (from the end of the war) does a British general actually propose the practice; and we have no proof that his superior applied the grim proposal.

Fenn's fresh new angle clarifies significant episodes in the war. In late 1775 in Virginia, the British royal governor, Lord Dunmore, invited black slaves to desert their planter masters and join his army in suppressing the revolution. To the horror of the planter class -- who dominated the revolution in the southern colonies -- about a thousand slaves escaped to enlist in Dunmore's "Ethiopian Regiment." To the planters' relief, smallpox soon killed most of the black troops, whom the British had neglected to inoculate. Fenn observes that "the very act of assembling the Ethiopian Regiment had brought together in one place a large, vulnerable population." At a critical, early moment in the revolution, the collapse of the Ethiopian Regiment preserved the slave system from its greatest threat. The untimely (for African Americans) epidemic preserved the paradoxical linkage of black slavery and white freedom in the Revolutionary movement.

Partial to neither side, smallpox assailed the Americans when they invaded Canada in late 1775. Despite hundreds of sick, their generals clung to the ban on variolation. Desperate to improve their odds of survival, dozens of men defied the orders and covertly inoculated themselves from the pustules of the sick. But this only compounded exposure for the troops who obeyed the orders to avoid variolation. As hundreds died, the commanders begged for reinforcements, but their arrival only increased the victims. Fenn explains: "With Variola coursing through the army, the arrival of new troops was akin to throwing gasoline on a fire." During the spring of 1776 the northern American army collapsed as the weakened survivors fled back into New York. One shocked soldier reported that "my eyes never before beheld such a seen, nor do I ever desire to see such another -- the Lice and Maggots [that] seme to vie with each other, were creeping in Millions over the Victims."

The northern debacle threatened to undo the remaining American armies led by Washington. The northern veterans brought home both smallpox and demoralizing stories about smallpox, spreading the epidemic to civilians and discouraging recruiting for the army. Men who might risk British gunfire balked at the more terrifying miseries of smallpox in a military camp. Facing a chronic shortage of manpower, Washington recognized that the Revolution could not survive another mass outbreak in the army. In early 1777, reversing his policy, Washington ordered a mass inoculation, which he managed to keep secret from British intelligence. "The army had pulled off the first large-scale, state-sponsored immunization campaign in American history," Fenn remarks. Given the probable consequences of either inaction or failure, the successful inoculation marks one of Washington's greatest accomplishments: a critical contribution to the narrow American victory.

Meanwhile, smallpox was spreading into the villages of Britain's Indian allies deep within the continent. In the spring of 1776, Indians helped rout the Americans retreating from Canada -- but by donning clothes plundered from the dying, many warriors contracted smallpox, which they carried home to their far-flung villages around the Great Lakes. Farther south, on the Carolina frontier, Cherokee warriors picked up smallpox by raiding infected American settlements. Variola then spread through the native world of the vast Mississippi River watershed, conveyed via "an unbroken chain of person-to-person connections." Apparently that chain brought the virus into the Spanish colony of Louisiana, at the mouth of the Mississippi, where smallpox proliferated during the winter of 1778-1779.

In the summer of 1779, the disease appeared in Mexico City, where at least nine thousand people died by year's end. North America's largest and most cosmopolitan center, Mexico City gathered and disgorged thousands of travelers annually, making it the perfect ground for breeding and spreading smallpox. By collecting and analyzing the mortality returns from Mexican parishes, Fenn painstakingly and insightfully reconstructs the disease's trajectory northward deep into the hinterland. At the end of 1780, the epidemic reached New Mexico, then the northern frontier of the vast Spanish empire. In Santa Fe's parish, mortality surged from only six deaths (from all causes) in December 1780 to thirty-nine in January 1781 to one hundred eighty-one in February.

Beyond New Mexico, European observers were few and transient: occasional sojourners in a vast geography possessed by diverse Indian peoples. On the Great Plains stretching northward into Canada, tribes of hunting-and-gathering nomads swirled around the more permanent villages of horticultural Indians dwelling along the few major rivers, principally the long and muddy Missouri. For most of the century, the villagers more than held their own in wars against the nomads. In addition to war, the various native peoples traded over vast distances. Native middlemen sent northward horses from New Mexico in exchange for Indian slaves taken by other natives in wars fueled by guns sold by British traders at forts along the sub-Arctic Hudson Bay for buffalo hides and beaver pelts. Mounted on newly acquired horses, and newly armed with guns, the Great Plains Indians could conduct war and trade at unprecedented velocity and over far greater distances. "It was," Fenn notes, "an intricate web of connections that could carry pox as well as pelts far and wide."

During the summer of 1782, native informants alerted the Hudson Bay traders to the demographic catastrophe raging in the immense interior. Thousands of Indians were dead or dying of smallpox. Traveling traders saw plenty of confirmation; one reported that "hundreds lay expiring together without assistance, without courage, or the least glimmering hopes of recovery." Panic compounded the mortality as relatives abandoned the victims, convinced that none could recover. Denied care, few did recover.

Fenn persuasively links the northern reports of 1782 to the New Mexican evidence of 1781 and to the Mexican parish returns of 1779-1780 as parts of one big epidemic, rather than several isolated episodes. She concludes that "the Mexico City outbreak generated a tidal wave of smallpox that reached as far north as Hudson Bay and as far west as Alaska." In the transmission northward beyond New Mexico, Fenn emphasizes the role of the Shoshone Indians, who lived in the Rocky Mountains and on the northwestern Great Plains. During the early eighteenth century, they became the pre-eminent middlemen in the north-south trade in New Mexican horses for Indian slaves. In 1781 their enemies, the Blackfeet, struck back by raiding Shoshone camps. The raiders won surprisingly easy victories, for most of the Shoshone were dying from smallpox. Unwittingly, the victors carried homeward the grim disease. A survivor told a trader that "we had no belief that one Man could give it to another, any more than a wounded Man could give his wound to another."

In tracking the disease, Fenn makes the most of the sparse and terse records made by the Indians, principally some "winter counts": buffalo hides spirally decorated with historical pictograms, one per winter. Each symbol represents the most conspicuous annual event in a tribe's experience, beginning in the late eighteenth century. At least thirteen of these survive to attest that smallpox dominated the native memory of the years 1781 and 1782. But generally Fenn must rely on the erratic accounts of Spanish officials and British traders perched at the northern and southern edges of the Great Plains, looking in with vague apprehension on the native world.

By necessity, Fenn speculates to fill in broad gaps between disparate clues. At one critical point in her story, she concedes that her interpretation "hangs upon a single shred of substantial evidence and the concurrence of a number of widely varying circumstances." Frank about her speculative methods and limited sources, Fenn invites readers into the detective work of making the most of a few traces in the documentary record. Rather than curse and dismiss this native world as historical darkness, she has found and lit the only candles available to her.

Fenn must be especially resourceful in deciphering the disease's probable route into the Pacific Northwest. Lacking colonies or resident traders, the Pacific Northwest remained, to eighteenth-century Europeans, the most mysterious and remote corner of North America. And so it is also terra incognita to colonial historians. Not until the late 1780s did sojourning mariners become routine annual visitors with a precise understanding of the coastline. Come to trade with the natives for sea otter pelts, these mariners found the signs of a massive smallpox epidemic: abandoned villages, bleaching skeletons scattered on the beaches, and native survivors with grim stories and pocked faces. But when and how had Variola arrived?

Fenn thoroughly and shrewdly examines the various European suspects. During the 1770s, Russian fur traders and Spanish explorers had probed the coastline, visiting the native villages. In 1778, the celebrated English navigator Captain James Cook sojourned with the Nootka people of Vancouver Island. None of these visitors reported any traces of smallpox. With careful research Fenn also dismisses the possibility that the mariners unwittingly introduced Variola to spread after their departure. She detects no traces of epidemic either in their home ports or aboard their ships during voyages far longer than the incubation period. By canvassing the multiple European forays to tell her smallpox story, Fenn concisely yet comprehensively depicts the rich complexities of a part of North America generally left mysterious in our histories.

By a process of European elimination, Fenn returns to the Shoshone as critical to transmitting the disease into the Pacific Northwest. European mariners discerned that the Pacific natives traded up the Columbia River with the Nez Perce Indians of the Rocky Mountains. During their subsequent trans-continental expedition of 1804-1806, Meriwether Lewis and William Clark noted that the Shoshone routinely traded with their neighbors the Nez Perce. Fenn plausibly reads that relationship back into the previous generation to interpret the Shoshone and Nez Perce as key links in the chain that brought Variola from New Mexico, up the Great Plains, into the Rocky Mountains, and down the Columbia to the Pacific. She explains: "Here the evidence regarding smallpox dwindles to nothing. But given Variola's transit thus far, it takes no great leap to imagine the disease traveling so short a distance [from the Shoshone to the Nez Perce]." Once again the smallpox story serves Fenn's larger ends: to reveal the continental shockwaves of colonialism far beyond the white faces, and to expose the enduring power of native networks of long-distance trade and diplomacy.

After canvassing the epidemic's spread across the continent, Fenn interprets its consequences. By her conservative estimate, during the war years smallpox claimed the lives of one hundred thirty thousand North Americans, most of them Indians. The epidemic killed far more people than did all the battles of the long war. By disproportionately afflicting some native groups, the disease empowered neighboring groups that suffered less. The village Indians of the Missouri Valley lived in greater concentrations, and so they died at a greater rate than did their enemies among the horse nomads. Exploiting their new advantage, the nomadic Lakota tribes destroyed many of the disease-weakened villages to become the most numerous and most powerful people along the Upper Missouri by 1800. Farther north, the Blackfeet similarly benefited from the greater deaths suffered by their rivals, the Shoshone to the west and the Cree to the east. The reduction of the Cree enabled the Blackfeet to directly obtain more guns from the British traders at Hudson Bay. Better armed than their enemies, the Blackfeet dominated the northern Great Plains, taking captives and hunting territory from the weakened Shoshone. At the start of the nineteenth century, the embattled Shoshone welcomed the Lewis and Clark expedition, detecting an opportunity to obtain American allies and guns to even their scores with the Blackfeet. In the pattern of native rivalries, shifted by the epidemic, the expanding Americans found new opportunities to dominate the continent.

Ultimately, as Fenn observes, "Variola was a virus of empire," for "in the long run, the pestilence seemed invariably to favor the great imperial powers of Europe and the United States." Especially the United States: with much help from smallpox in Virginia, the Americans won their revolution without conceding liberty to their many slaves. After the war, thanks to the further reduction of Indian numbers, the Americans more readily expanded their settlements westward, reaching the Pacific by the 1840s.

Fenn recovers and tells a story that is timely as well as powerful and sobering. Contrary to official and popular myths, smallpox is still with us. Advances in methods of inoculation and measures of public health did combine to curtail the disease dramatically during the twentieth century. Deemed eradicated in 1979 by the World Health Organization, smallpox last claimed victims in September 1978, when a medical technician died after contracting the virus from matter inadequately secured in a nearby laboratory in Birmingham, England. In shame and despair, the laboratory's head committed suicide.

Variola will almost certainly kill again -- if not by another accident, then by intentional proliferation as a biological weapon. After 1979, the World Health Organization reduced the officially authorized stocks of Variola to just two: one in the United States and one in Russia. Both were scheduled for destruction in 1999, but the American government balked. Suspecting a larger number of clandestine stocks in other hands -- some of them terrorist hands -- the American military preferred to preserve its own potential for biological warfare. If unleashed into our place and time, Variola will delight in human hosts far more crowded, rapidly mobile, capable of mass warfare, and free from the immunities of smallpox experience than in the eighteenth century. Taking a cue from no less an American authority than George Washington, our leaders would do well to accelerate the production and the administration of comprehensive vaccination against this dreaded disease.

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