Pioneer Scientists and the Great Animal Plagues

Front matter

PIONEER SCIENCE

AND THE GREAT PLAGUES

NEW DIRECTIONS IN THE HUMAN-ANIMAL BOND

Part II. Farrier To Veterinarian 6. 7 8. 9

Emigrants West: Ohio Country, Iowa Territory, and Tejas

. The Canadian Midwest: Divergence of Lower and Upper Canada

Pioneers in the Midwest Frontier: Physicians in Veterinary Practice

. New Plagues, Civil War, and the United States Department of Agriculture

Agriculture and Veterinary Science in the Midwest

PART 111. PIONEERING VETERINARY EDUCATION

II

Urban East Versus Rural West: Montreal and New York Diss Toronto and Iowa

The Pioneer State Colleges: Iowa, Ohio, Pennsylvania, and Cornell Plagues and the Bureau of Animal Industry

Bacteriology in the Heartland

The 1890s: Horse Markets and Enrollments Drop

PART Iv. LIVESTOCK AND VETERINARIANS GO WEST 16. 17. 18. 19

Private Veterinary Schools: Chicago, Kansas City, and Indianapolis Public Veterinary Schools: The Second-Generation Pioneers

The Bureau of Animal Industry and Hog Cholera

Veterinary Education, Charles Stange, and the Flexner Report World War I: Biowarfare, Prejudice, and the US. Army

Veterinary Corps vii vi CONTENTS

Part V. Ascendance

21. Agricultural Depression Amidst a National Boom: The 1920s

22. 1929: Prelude to Bad Times

23. Public Health and Distrust of Government: The Tuberculin War 24. A Depression Paradox: Culture and Science

25. New Deal: Discoveries in Infectious Disease

PART vi. DUTY REQUIRED

26. War: The Home Front

27. Veterinary Corps and Bioterror

28. Postwar Investigations of Enemy Biological Warfare 29. Prelude to the Science Revolution

30. The Atomic Age

PART vil. TRANSFORMATION

31. New Programs, New Laboratories: Malaria, Polio, and New Viruses

32. Comparative Medicine: Models for Leukemia

33. Grassroots Mandates: The National Research Centers for Livestock Diseases

34. Old Plagues in the Wild: The National Wildlife Centers

35. New Plagues: Scrapie, Mad Cow Disease, and the Prion

PART vill. EPILOGUE

36. The Farm Crises of 1980-1995: Distrust of Science

37. The Gender Shift

38. Biopolitics

39. Bioterror, Anthrax, and the National Animal Health Networks

40. Anti-Science Scams and Keys to Progress

Appendixes

Notes

About the Author

139 140 147 152 158 161

167 168 176 181 187 196

205 207

216 223

237 239 242 247 255 264

273 291 331 359

PREFACE

A health care in North America evolved from farriers and itinerant cow leeches to science-based veterinary medicine in one century, from 1860 to 1960. This history focuses on the scientists and institutions that pioneered veterinary education and research. It memorializes the events and ideas that propelled science forward and those that blocked progress. An important part of the story is how cycles of discovery were enhanced or retarded by viability of the economy, by demands of war, and by idiosyncrasies of political culture—elements of society that are linked together.

Veterinary science in the rural Midwest arose from agriculture, but in urban Philadelphia it came from medicine; similar differences occurred in Canada between Toronto and Montreal. The Iowa Agricultural College was the first to establish a state-supported school of veterinary medicine in the United States that survived; its first scientists were agriculturalists and its graduates founded colleges and departments of veterinary medicine in the Midwest, Great Plains, Atlantic Seaboard, South, and the Palouse of the Northwest. In contrast, the University of Pennsylvania veterinary school was established as a cooperative venture with the medical school; its first science faculty were physicians who brought home the medical sciences from Europe.

As land grant colleges were established after the American Civil War, individual states followed divergent pathways in supporting veterinary science: one, a trade school curriculum that taught agriculturalists to empirically treat animal diseases; the other, a curriculum tied to science. The relevance of this, a pattern continued for a century, is that today some institutions have moved back to the trade school philosophy. Avoiding lessons of the 1910 Flexner Report on medical education reform, university-associated veterinary schools are being approved that do not have control of their own veterinary hospitals, diagnostic laboratories, and research institutes, components that are critical for training students in science. Underlying this change were twin idiosyncrasies of culture— disbelief in science and distrust of government—that spawned scientology, creationism, anti-vaccination movements, and other anti-science viii PREFACE scams. All of these scalawags had destructive impacts on science in general and in veterinary medicine in particular. And there were other bogeymen within science: fraudulent scientists that stole the work of others, dishonest entrepreneurs, and latter-day snake oil salesmen.

The most recent impact on veterinary science has been the ascendance of women. Not permitted to study for the profession in early times, female students exploded after World War II, from near o in 1960 to nearly 90 percent of all veterinary school graduates in 2000. Women continue to play an increasing role in scientific research in the great plagues: veterinarian Amy Vincent, a scientist at the National Animal Disease Center, was awarded membership in the National Academy of Medicine in 2020 for her work on surveillance, vaccines, and the pandemic potential of swine influenza models.

THIS BOOK COVERS THE CENTURY when the infectious diseases anthrax, tuberculosis, smallpox, tetanus, plague, and polio were conquered and illuminates the important role that veterinary research played in that battle. The narrative is driven by astonishing events that centered on animal disease: the influenza pandemic of 1872, discovery of the causes of anthrax and tuberculosis in 1880s, the conquest of Texas cattle fever and then yellow fever, the German anthrax attacks on the U.S. during World War I, the tuberculin war of 1931, Japanese biological warfare in the 1940s, and today’s bioterror dangers. These events illustrate how progress in biomedical science comes and goes in cycles. From 1860 to 1960, new investigative techniques appeared, shined brightly, and were replaced by technologies that were more advanced. When seminal discoveries were made, each generation of scientists was presented with new opportunities that lasted decades. This is the story of how pioneer veterinary scientists contributed to and capitalized on those discoveries for one century.

Norman Cheville

January 2021

ACKNOWLEDGMENTS

I am grateful to the many colleagues who have enriched my life as a veterinarian, especially to early collaborators in scientific research at the National Animal Disease Center: Milt Allison, Randall Cutlip, John Kluge, Janice Miller, Vince Meador, Harley Moon, Martin Van Der Maaten, and the more than thirty graduate students and visiting scientists who helped in many ways. Special thanks to the following Iowa State University faculty, whose personal interviews added so much to this volume: George Christiansen, Jarod Danielson, Robert Duncan, Heather West Greenlee, Richard Ross, and James Roth. Veterinary scientists who contributed to research on the great animal plagues include Ian Barker, University of Guelph; Bernard Easterday, University of Wisconsin; Paul Hildebrandt, U.S. Army; Tracy McNamara, formerly of the Bronx Zoo; Jack Rhyan, National Wildlife Disease Center; John Shadduck, dean emeritus, Texas A&M University; Terry Spraker, Colorado State University; and Keith Prasse and Lisa Nolan, deans at the University of Georgia.

Archival material from collections of the HathiTrust digital library, the E. A. Benbrook papers, and the Iowa State University Library Archives were essential. Timothy Horning, public services archivist at the University of Pennsylvania, was marvelously efficient in helping with the history of PennVet, and Halle Mares with the Ohio State University Archives located material on H. J. Detmers. Susanne K. Whitaker of the Rare and Manuscript Collections at the Cornell University Library provided photographs and data on James Law and the veterinary faculty. Jennifer Wiggins and Tommy Brown in Special Collections and Archives at Auburn University Libraries authenticated photos of the first veterinary class at Auburn University. Renee Ziemer, historian of the Mayo Clinic, led me on important paths to information on William Mayo as a veterinarian.

Four books by midwestern authors were critical for historical accuracy: History of Veterinary Medicine at Iowa State College, C. H. Stange, 1929, lowa; Veterinary Military History of the United States, Louis Merillat and Delwin Campbell, Illinois, 1935; 4 Short History of Veterinary Medicine in America, x ACKNOWLEDGMENTS

B. W. Bierer, Missouri, 1955; and The American Veterinary Profession, J. F. Smithcors, Michigan, 1963.

Regional books of exceptional value were The Cary Legacy, Sam Hendrix, Alabama, 2018; Chronicles of Faith, Frederick Patterson, Alabama, 1991; A Century of Excellence, Ronnie Elmore and Howard Erickson, Kansas, 2005; History of the School of Veterinary Medicine of the University of Pennsylvania, 1884-1934, Louis Klein et al.,1935; and A Cornell Heritage: Veterinary Medicine 1868-1908, E. P. Leonard, 1979.

I am indebted to my wife, Beth, and three of our children—biochemist Anne Nelson, literacy professor Julie Cheville, and physician John Cheville—for reviewing the manuscript and steering me in the right direction. Finally, it has been my good fortune to work with Purdue University Press director Justin Race, graphic designer Chris Brannan, acquisitions assistant Susan Wegener, and senior production editor Kelley Kimm, as well as the sales and marketing staff. Collectively, their positive approach, guidance, reviews, critiques, and adaptation to the author's foibles brought the book to its final form.

Part I

PROLOGUE he Puritan ship Mayflower landed on Cape Cod in 1620, bringing Dorking

chickens, Tamworth pigs, and two dogs, an English mastiffand an English spaniel. All sturdy breeds, they had been healthy when leaving England and survived in Plymouth Colony freed from European plagues. Their risk of disease in the New World may also have been diminished by a reduction in the population density of both native humans and animals from a catastrophic plague that had swept through eastern Massachusetts the previous decade.’

The “Indian disease” had devastated tribes prior to the Mayflower’s arrival; it had also killed muskrats, mink, and raccoons. Tribal members developed high fevers, headaches, and skin rashes and, near death, bleeding from the nose. Historians believed the disease to have been leptospirosis,” acquired from rats leaving the ships of previous French explorers.’ The bacteria that cause leptospirosis—spirochetes similar to those of syphilis—attack the liver, kidney, and red blood cells; harbored in the kidney tubules, they are released with urine into aquatic environments like the marshes and cranberry bogs frequented by the agrarian native tribes of eastern Massachusetts and Rhode Island. Tisquatum—called Squanto—was a native American interpreter for the Puritans; kidnapped and taken to Spain and England, he returned to find his Pawtuxet tribe no longer existed.

There was no cow on the Mayflower—and no cow’s milk, cheese, or butter. Three years after arrival, on September 10, 1623, the English commercial cargo ship Anne left the struggling Plymouth Colony with a load of clapboards and beaver hides for England. Aboard was Edward Winslow, returning to England as an agent for the colony with instructions to bring back healthy cattle. Arriving in London, Winslow purchased three red Devon heifers and one bull—all free of rinderpest, cowpox, and other diseases that afflicted European cattle. He accompanied them home on the ship Charity, arriving at Plymouth in March of the next year. Short and sturdy, the red Devon was a multipurpose breed that not only provided milk and meat but could be readily trained as obedient draft oxen. In four years the colony’s herd grew to sixteen with the arrival of four black Kerry cows from England. The red Devon survived to become the draft oxen and foundation stock of New England cattle for two centuries.*

At the time there was no concept of a veterinarian—no science or education to support animal health care and no government agency to call or blame when disease appeared. There were homemade remedies. In the 1672 book New England Rarities Discovered, author John Josselyn described cranberries as “excellent against scurvy” and “also good to allay the fervor of hoof diseases.” The Mayflower had carried a copy of The Surgeons Mate by John Woodall, the first surgeon general of England; written at the behest of the East India Company's navy, its only treatments were herbalism, phlebotomy, and prayer. Medicine, like governance in Plymouth Colony, adhered to biblical mandates; science was not used for analysis or logic in solving problems of health, thievery, or fornication. For animal health care in England there had been only untrained cow leeches. Control of the great animal plagues that periodically swept through the countryside was limited to feeble attempts by local agriculturalists to persuade herdsmen and drovers to segregate and remove sick and dying animals.’

History does not record the arrival of the horse in the early American colonies. Heavy forests made horseback travel difficult and there was less need for the horse. But in Europe horses were transportation, the means for war, and a bedrock of the economy, and it was the unschooled farrier who cared for common horses. On wealthy royal estates and in cavalry stables and equitation academies, horse masters had developed an art for the care of the lame and sick. Their diagnoses, arrived at by experience, were tainted by superstition, hindered by religious dogma, and unproven by experiment, and they were frequently wrong.

In the mid-1600s, skills of the horse master began to appear in books. The first classic, Le parfiat maréchal (The complete horseman), was published in Paris in 1664 and appeared in German and English translations. The author, horse master Jacques Labessie de Solleysel, included a chapter on disease, complaining that in France, the veterinary art was too much in the hands of the farrier’

1. THE VETERINARY SCHOOLS OF EUROPE he Seven Years’ War from 1756 to 1763 put European states on the side of

either France or Britain in a debacle that cost nearly a million lives. Horses of both sides died in catastrophic epidemics of infectious diseases. Tetanus, glanders, and rabies killed military horses and also infected and killed horsemen. Tetanus, an ever-present danger, arose from contaminated wounds. Before streets were paved and hooves protected from nails and debris by horseshoes, tetanus took a terrible toll. The painful unremitting muscle contraction of tetanus—called lockjaw in humans—led slowly and relentlessly to excruciating paralysis of muscles in the jaw, diaphragm, and rib cage. Dying was prolonged and painful. In the 1757 Battle of Prague, four thousand wounded soldiers died of tetanus and deaths in horses were correspondingly high—the astonishing losses forced cavalry horse masters to seek answers in science.

A highly infectious plague was equally catastrophic for cattle in the same century. Three devastating outbreaks of rinderpest — German for cattle plague—hit Europe in 1709-1720, 1742-1760, and 1768-1786. Affected cattle stopped eating and rapidly developed high fevers, diarrhea, and ulcers in the mouth; mortality rates were often 100 percent in newly infected herds. Losses were so great that production of milk and meat seriously declined. During the first epidemic, the public’s belief of rinderpest as divine punishment with its mandate to bear the burden was overridden by practical agriculturalists who imposed trade barriers—the rinderpest decrees—to avoid contact between local herds and caravans of cattle traveling on military sorties or on the overland oxen trade routes. Cull-and-slaughter programs were devised that proved ineffective. By the last rinderpest epidemic, both royals and politicians had taken notice of a need for veterinary science and education to combat diseases of cattle. The message had been clear: animal plagues could destroy the growing prosperity.

By the mid-1700s, France’s population and economy had doubled, and Louis XV’s finance minister had stabilized coins. Rising prices for agricultural products were highly profitable for large landowners who introduced changes from Britain — fertilizers, crop rotations, and the planting of new-world maize and potatoes. The Industrial Revolution was being fueled by trade with America and the steam engine of a Scottish engineer. With some irony, agricultural economic success brought dangers of both war and animal disease. In the countryside, the growth of livestock populations had increased the likelihood of serious and recurring infectious diseases in cattle and sheep—anthrax, sheep pox, scabies, blackleg, and rinderpest—all diseases that could destroy food production and, along with it, the French economy. Losses from disease were forcing science into workaday animal husbandry.

As new knowledge about contagious diseases emerged, facts began to be objectively verified. In the next century, primitive scientific experimentation provided data that created experts in animal health. When the mechanical movable type printing press introduced mass communication with unrestricted circulation of information and ideas to the masses, there was a sharp increase in literacy that overwhelmed the monopoly of the learned elite, broke Latin’s status as the lingua franca, and extended into agriculture to give birth to veterinary medicine. Scientists organized academies and meetings where papers were read and from which reports were published. In the new British journal The Veterinarian, an English veterinarian reported the first subtle signs of muscle rigidity in a horse with tetanus acquired from a nail injury to the hoof while being shod by a careless farrier: “Head more elevated than usual, ears erect and pointed forward, membrana nictitans protruding in part over the eye, nose thrown out, nostrils dilated, his tail a little elevated, he straddled in his gait . . °

The free exchange of views was a powerful stimulus to discovery, and by the end of the nineteenth century, veterinarians could explain that tetanus was caused by a bacterium. Scientists named it Clostridium tetani and discovered that it thrived in the dead tissue of wounds, releasing its toxin to spread through the body, causing lethal muscle contraction. Pioneer veterinarians were contributing to and capitalizing on the new scientific discoveries. Anti-science clerics and superstitious magicians were still forces, but education was becoming garlic to society’s anti-science vampires, who were blind to natural science—or so it seemed.

THE FIRST FORMAL SCHOOLS to educate veterinarians were established in France—one in Lyon, the other outside Paris in Alfort. Claude Bourgelat, the founder of both, was born and educated in Lyon, where he was admitted to the bar, succeeding his father, a prominent attorney, in the practice of law. Biographers write of him as a lazy youth of high intelligence and a superior and widely admired horseman. He was connected socially and as a young man was appointed écuyer (horse master) of the Academy of Equitation in Lyon in 1740.

Bourgelat’s wealth and his position as a director of the Lyon city library had given him access to books. The ancient Roman and Arabic veterinary texts, destroyed in Medieval Europe, had been rediscovered and translated into English, French, and German. Available to only the wealthy, they were sequestered in great city and personal libraries in England and France. Among the Roman works that had been translated into European languages was Epitoma rei militaris, a book on cavalry and military tactics written in Latin in the fourth century by the eastern Roman citizen Flavius Vegetius; George Washington owned a copy and used Vegetius’s “Let him who desires peace, prepare for war” in his first inaugural address. Vegetius wrote one other important book, Digesta artis mulomedicinae, a collection of equine anatomy, disease, and clinical care—and Bourgelat had a copy.

As he matured and traveled, Bourgelat gained an appreciation of biology and science. In Lyon he published a three-volume tome, Elémens d‘hippiatrique, ou, Nouveaux principes sur la connoissance et sur la médecine des chevaux (Elements of hippiatry and new knowledge of equine medicine). Strongly advocating for veterinary education, Bourgelat operated a private school in Lyon for several years. In 1761 he was named inspector of the library of Lyon, in which role he was accused by Voltaire of preventing entry into France a consignment of books containing the historic La tolerance. But his connections and position among the elite horsemen were unassailable. He had furnished excellent remounts for cavalry regiments of the King and had eradicated glanders as a scourge of military horses.

Bourgelat was supported by another native of Lyon with a close relationship to its Academy of Equitation: Henri Bertin, the comptroller of finances under Louis XV. A lieutenant general of the Paris police, Bertin was a favorite of the king’s mistress Madame de Pompadour and used this influence to obtain a Royal Charter for Lyon. King Louis XV gave the new school the title of the Royal Veterinary College when it opened to students in January 1762. Two years later, using his political power to override opposition from local farriers, Bertin called Bourgelat to Paris to found the second French school, Ecole Vétérinaire Nationale d’Alfort.

In the next decade the French schools prospered and were visited by influential veterinarians from other European countries who returned home to establish veterinary schools in Vienna, Copenhagen, London, Edinburgh,

The Cow-Doctor depicts the high status of veterinarians in Europe in the mid-1880s.

Skara (Sweden), and Brussels. In Germany there were new schools in Berlin, Hannover, Munich, and Stuttgart, and Russia founded schools in Kharkov (now Ukraine), Dorpat (now Tartu, Estonia), and Kazan—all dedicated to veterinary science, some making astounding discoveries. In France, rinderpest led the government to create a third veterinary school in Toulouse directed toward diseases of cattle.’ The first veterinary school in the United States was a direct legacy from Toulouse; the first in Britain was from Lyon.

In England, successful farmers and “gentlemen of rank, fortune, and ingenuity” assembled in Odiham’s George Tavern on May 16, 1783, to discuss how to encourage agriculture and industry in Hampshire. Establishing the Odiham Agricultural Society, they resolved to reform farriery and animal care by establishing a school to teach veterinary science. Granville Penn, a leader of the group—and grandson of William Penn—was sent to London to seek out the immigrant Lyon veterinary school graduate Charles Benoit Vial de Saint-Bel. The expatriate Frenchman had taught in the veterinary school at

Alfort but, quarreling with Bourgelat, he returned to Lyon as head of the

Academy of Equitation and to serve as one of the horse masters of Louis XVI. Failing to be appointed at Alfort when Bourgelat died and tainted by connections to nobility — Bourgelat is alleged to have contributed to the charge that Vial was an enemy of the government— Charles Vial fled revolutionary France for England with ideas of starting his own school for veterinarians. Planning together, he and Penn established a London committee of the Odiham Agricultural Society to secure funds for a veterinary school.

Notoriety for their cause occurred in 1789 when the Western world’s most famous racehorse, a tall English thoroughbred named Eclipse, died of colic. Eclipse had dominated the racing seasons of 1769 and 1770 and stood at stud for nineteen years. To find the cause of death and to explain his extraordinary athleticism, the owners found only one qualified veterinarian for the task: Charles Vial; his autopsy of Eclipse revealed a massively enlarged heart. The publicity of Vials report was an important assist in the birth of a London veterinary school.”

Financial support for the new London school came from livestock organizations and fifty guineas from the Duke of Northumberland. Perhaps more important, there was strong encouragement from London medical scientists, including the famed anatomist/surgeon John Hunter—he had discovered the circulation of blood in the body—and in the end, from Parliament. The veterinary school building was constructed in 1791 in Camden Town of St. Pancras Parish, close to stables that served the London transport system. The next January it opened as the Veterinary College, London, with four students studying toward a veterinary certificate. Successful in the first decade, the school was granted a Royal Charter and christened the Royal Veterinary College.

Two years later, Charles Vial was dead of glanders. He had suffered in great pain for seventeen days with boils and buboes in different parts of his body—the same massive and disseminated lymph node swellings in the horse he had treated and from which he had acquired the disease. Vial died on August 21, 1793. John Hunter also died that year; he had been the leading surgeon and medical scientist of the eighteenth century and had strongly supported the college, arranging for veterinary students to attend his medical lectures.

Losing Vial’s leadership and Hunter’s scientific support, science in the Royal Veterinary College declined, and with it the competency and luster it had accrued. Edward Coleman, its new principal, seemed to lack inquisitiveness for science and creativity, as well as enthusiasm for change. The journal

The Veterinarian was founded in London in 1828; in the second volume (1829), editors Percival and Youatt, both veterinary surgeons, condemned the weaknesses of the college in London, accusing the two faculty — Professor Coleman and his assistant — of “abuses and mismanagement” and writing that the school should “correct the existing evils, and establish our claims to respectability.” Other damning editorials soon appeared, one stating that “many valuable horses have been destroyed by the ignorance of men who have been pupils at the Royal Veterinary College for a short period.”" What was needed, they said, were longer months of study, more anatomical demonstrations, and practice in techniques of surgery, laboratory work, and the forge. All agreed on the need for a committee to contact Parliament to enact a law to restrict farriers from practicing as veterinarians.

Farriers responded in the journal. An anonymous retort signed only by “A Farrier” maintained that farriers provided better horse care than that provided by the Royal Veterinary College. But farriers knew nothing of the diseases of food-producing livestock that were a major concern of educated veterinarians. There were cattle plagues other than rinderpest in the English countryside, some of them contagious to humans, making it dangerous to be a cow doctor. Diseases killing animals were not only killing farmers and veterinarians, they were being passed through meat and milk into the cities.

Raw milk, with its contaminants of disease-causing bacteria, could be hazardous, especially if it came from cows with tuberculosis. Increasing in the 1700s because human urban populations were growing, tuberculosis, known as the white plague, was killing hundreds of citizens. The disease most often insidiously attacked the lungs but could also settle in the bones, intestines, brain, or any other organ. Many cases of tuberculosis were caused not by the human bacillus but from the bovine tuberculosis bacillus, gotten through impure raw milk. In Germany one farm family, all “herculean in stature and boastful of strength and health,” had been stricken when they purchased a group of Simmental cattle, all infected with bovine tuberculosis. Within a year, the thirteen-year-old daughter and eighteen-year-old son developed pulmonary tuberculosis and died. The next year a twenty-three-year-old son died. The year after that the mother, remaining daughter, father, and finally the third son died.”

Pesky skin diseases moved from cow to herdsmen and milkmaids. There were scabies parasites that crawled into the skin just where they readily jumped to humans, and ringworm that when brushed onto the arms grew in nasty inflammatory rings until treated with turpentine. And there was cowpox. Teats of milk cows developed painful pocks that spread to the hands of milkers. Starting as small vesicles, they progressed to pustules and then to scabs that peeled away in a week or two; there was no fatality, and milkers with cowpox recovered without developing serious illness. There was even an old wives’ tale that cowpox was beneficial—milkers having had cowpox were not susceptible to the plague of smallpox. The tale was true. It was the impetus for the greatest medical discovery of the century—and perhaps ever—which was reported in London in 1798 and had begun with a disease of cattle.

2. EDWARD JENNER: ZOOLOGIST, PHYSICIAN, PIONEER n the mid-1700s, human smallpox was a horrific and disfiguring lethal

disease that decimated global human populations. Called by physicians variola (from the Latin varius, for speckled), smallpox spread from patient to patient through the mouth and nose. Physicians called it a contagion—a disease caused by contact. No one knew about the cause or that, after silently multiplying locally in the tonsils for a week or so, massive amounts of variola virus were released into the bloodstream. As it spread throughout the body, there was debilitating fever, headaches, and collapse; lodging in the skin, smallpox virus speckled the victim with ugly vesicles, pustules, and scabs, if the patient survived that long.”

To lessen the mortality, physicians offered a risky preventative, variolation—scraping a tiny piece of scab from a sick smallpox patient into the skin of the forearm of a healthy person.'* A local smallpox pustule would develop on the variolated arm and the variolated patient would sicken but survive; the peripheral site of infection would bypass massive viral replication in the tonsils, providing time for an immune response that could prevent disease from being fatal; but not always—variolation still carried a risk of serious disease and death from smallpox.

In the dairy farming country of Southwest England, cows carried their own pox virus. Cowpox appeared on the teats and udder of milk cows as vesicles, then pustules, and finally scabs that healed within a few weeks. The pustules would “degenerate into phagedenic ulcers, which prove extremely troublesome. The animals become indisposed, and the secretion of milk is much lessened.”

The problem was, cowpox was a zoonotic disease— transmissible to people.

Milkmaids and male servants assisting with milking developed cowpox—with identical vesicles, pustules, and ulcers on their hands; the “system becomes affected” with headache, muscle pain, fever, and swelling of axillary nodes, yet humans, like cows, recovered. Local folk knowledge was that milkers, drovers, and other cow handlers that had developed cowpox would not “take the smallpox.” It was common opinion that milkmaids having had cowpox could safely nurse smallpox patients without fear.

In the Dorset village of Yetminster—far removed from the sophisticates in London—farmer Benjamin Jesty and his two servants became infected with cowpox. In 1774, impressed that all had passed through the next smallpox epidemic untouched, Jesty took his wife and two sons to a cowpox-infected dairy farm nearby and, making skin abrasions with a darning needle, inoculated them with purulent material from cowpox scabs. When the cowpox lesions healed, they too passed through smallpox episodes without taking the disease. Yet the citizens of Dorset saw farmer Jesty’s act as unnatural. Rather than attracting fame, he was ridiculed by friends and vilified by gentry for having violated the laws of nature.

In the next two decades, other creative people in England, Denmark, and Germany used cowpox to protect against smallpox. John Fewster, an apothecary in Thornbury, Gloucestershire, inoculated children with cowpox, suggesting that it protected against smallpox. In 1791 the German teacher Peter Plett inoculated three children with cowpox exudate fluid, and he too saw them protected. Turns out, experienced physicians in the dairy farming areas were aware that cowpox could be used for protection, but these were anecdotal cases, unpublished, unpopular, and disbelieved by the medical establishment. But that changed when a scientist in Gloucestershire went at the problem systematically.