Disease! is a series of diaries, appearing on Thursdays, about a category of overlooked epidemics -- plant and animal diseases. While they rarely make the news, these epidemics, often caused by invasive pathogens, have had and continue to have enormous ecological and economic impact. And in a world with changing climate and blending borders, we can only expect more to come.
Sometimes it's easier than others to figure out why a story is relatively overlooked in American media. I've never understood why so many horrifying plant and animal epidemics get so little notice in the press, even though it is -- too often -- American flora and fauna that are their victims. The recent news regarding this week's installment of Disease!, however, got only passing attention in the United States in part because it was never an American problem. Not, mind you, that it got the attention it deserved anywhere else, either.
But for over five thousand years, it certainly was a problem elsewhere in the world: in Asia, in Europe, then in Africa. The Americas, Australia, and a few other lucky regions never saw the scourge of a disease that struck humanity hard -- not by infecting us, but by infecting and killing something central to our civilization.
Cows.
The history of humanity is in some sense the history of cattle. We harnessed their physical strength to pull and to plow. We fed ourselves with their meat and milk, and fed our crops with their manure. We clothed ourselves in their skins and leathers. But for millennia, sometimes, they died. They died a horrible, ulcerating death, spread by wind and water. They died by the thousands, sometimes the millions, across regions the size of continents. And because the domestication of cattle is so deeply entwined with the success of human culture, when they died ... so did we.
Attentive readers may have noticed something about this introduction seems different than previous installments of Disease!, and they would be right. The tale of this disease is written in the past tense. Because this story has a happy ending.
Unlike many epidemics, where the fluid mobility of the modern world was the catalyst for the disease's rapid spread, the history of rinderpest, or cattle-plague, is longer than history itself. And so the earliest chapters of this story are lost to the misty passage of time. It is largely believed that the virus originated somewhere in central Asia in antiquity. Regardless, as cultural growth spread the knowledge of domestication, and traders carried animal products to neighboring lands, a silent hitchhiker traveled with them. During the heights of epidemics, rinderpest was staggeringly lethal, with 80-90% mortality rates in infected herds not unexpected.
It is thought that the disease was present in Egypt as early as 3000 BCE. It was probably the Struma, described by Aristotle in the 4th century BCE. The "steppe murrain" introduced to Europe by the invading Huns in 370 CE was likely the same disease. The first well-documented epidemic outbreak of the disease was a decade-long plague beginning in 376, described by the Roman writer Severus Sanctus Endeleichus. Its tendency to follow in the footsteps of war was clearly established when the Mongol invasions sparked Europe-spanning outbreaks in 1233 and 1238, the latter of which reached England by way of cattle imported from what is now France.
For some spans of time, it would adapt to be less visible, less lethal. This adaptability likely played a role in its endurance -- an adaptability that mankind also paid a direct price for. At some point [pdf], perhaps as early as the 7th century or as late as the 10th, somewhere in southern Europe, a strain of rinderpest mutated. The new virus was closely related, but different in critical ways. It was not quite so destructive, and not nearly as deadly. And it was no longer a disease of cattle. The story of this wayward mutant is for a different diary, in a different series, because that virus isn't called rinderpest anymore. It is called measles.
Most of the viral population stayed as it had always been, though. The long European tradition of war was made bloodier by the disease, which flared up in the wake of military campaigns over and over and over again. The tendency of all the cattle in war-torn regions of the continent to occasionally die went a long way to ensuring the poverty and hunger of Europe's lower classes for centuries. Nor did the advance of civilization do anything to slow its spread. Rather, by the time the calendar had moved forward to the 18th century, Europe saw cattle herds struck by roiling outbreaks of cattle-plague: one from 1709-1720, another 1742-1760, and an especially severe epidemic that began in 1768 and didn't truly end until 1786. The Dutch were hit especially hard by the 18th century epidemics, as were the British in the next century.
Rinderpest closed the 19th century on a somber note as well. In the 1890s, Italian military action in Abyssinia (now Ethiopia and Eritrea) introduced the disease to Africa; although it had been endemic in Egypt for millennia, the desert's barrier had prevented its southward spread. Fueled by pastoral herds and a wholly immunologically naive population, rinderpest raced south through Africa, all the way to South Africa. Perhaps 80% of the cattle in Abyssinia died. The famine left in its wake is estimated to have killed a third of the native human population and ensured the Italian's hold on Eritrea. A second wave of the disease in the 1930s nearly wiped out the herds of the unconquered, famously cattle-herding, and militarily-adept Nuer tribe in Sudan; the resulting forced changes in Nuer economics and culture contributed to the instability in the region that we have now become familiar with.
Rinderpest was an agent of incalculable suffering, both of animals and of the people who starved in its wake. And it was considered for use as an agent of intentionally inflicted suffering as well. Some historians have suggested that Genghis Khan knew he was bringing the disease to Europe; his gray oxen were comparatively resistant to the disease, and the starvation and chaos left in the wake of the disease opened the way for invasion. In the modern era, allegations -- never-proven -- have been made that the Italian introduction of rinderpest into Abyssinia was similarly intentional. And it was among the agents considered for use as biological weapons, both by the United Stats (at Fort Terry) and by the Soviet Union (Project Ecology). But the horrors of biological/economic warfare were put back to rest. Rather, as I said, this story has a happy ending.
By the early 1700s, efforts to control rinderpest [pdf] began to be developed. As science began to understand the mechanisms of infectious disease, Giovanni Maria Lancisi (personal physician to Popes Innocent XI, Clement XI, and Innocent XII; best known for his discovery that mosquito control reduces the incidence of malaria) suggested that rinderpest outbreaks should be responded to with the immediate destruction [abstract only] of all exposed animals. Still, few governments in 1715 were in a position to mandate an action perceived as so costly. That perceived cost clashed with that century's epidemics, spurring research for alternative means of control. Beginning in 1754, trial efforts at rinderpest inoculation began. Because of rinderpest's overwhelming mortality rate, the process never became widespread, and sometimes caused more harm than good. It did have direct benefits to the body of knowledge, however. Measles inoculation programs (remember measles?) were a direct result of the work done with rinderpest. Also, Geert Reinders's inoculation trials led to the discovery of maternally derived immunity.
In the 20th century, armed with better knowledge of disease, eradication efforts began in earnest. The causative virus was isolated by researchers Nicolle and Adil-Bey in 1902. The World Organisation for Animal Health was formed in 1924 to coordinate these efforts. In 1950, another organization, the Inter-African Bureau of Epizootic Diseases, focused on driving the disease from Africa. These efforts were aided by Walter Plowright's 1962 publication in Bulletin de l'Office Internationale des Épizooties, describing a safe and stable vaccine with no side effects (for which he won the 1999 World Food Prize), developed using the same techniques that had allowed for a vaccine against polio.
Mass vaccination campaigns stopped an outbreak that had begun in Afghanistan in 1969, clearing most of Asia by the early 1970s. Eradication suffered a setback in the 1980s, when an outbreak in the Sudan swelled into what would be the last rinderpest epidemic, killing millions of domesticated cattle across all of Africa. A decade later, however, a dedicated vaccination effort had pushed the disease back to only a few isolated hot-spots in Sudan, Somalia, and Kenya. The last known case of rinderpest occurred in Kenya in 2001. A secondary vaccine campaign was launched in Somalia in 2006 out of concerns that the virus might have lingered in that troubled region, but no new cases were ever observed. In October 2010, the United Nations officially announced that rinderpest, like smallpox before it, had been "wiped off the face of the earth".
The eradication got relatively little mainstream press: page A6 of the New York Times, and a thin, six-paragraph (counting generously) wire release by Reuters, mostly. Perhaps this was because it never got any closer to the United States than Brazil (one outbreak in 1920, successfully contained) and never became established in Australia (one outbreak in 1923, successfully contained), or because it had been so long since it had troubled the western world. But if someone from the 18th century Netherlands, or from Africa in the 1890s, or from any of countless other places and times throughout the history of Europe and Asia, could remark upon the achievements of our civilization, the eradication of cattle-plague would surely rank high among them.
Next week on Disease!: A bad Hollywood sequel
Previously on Disease!:
An "unprecedented epidemic", the story of white-nose syndrome
Four billion dead, the story of chestnut blight
EDIT: Additional links provided. Because the only outbreaks of this disease in the Internet Age have been in perennially-overlooked Africa, a distressing amount of the history of the disease is simply not adequately represented online (or behind journal subscriptions, which I know are frustrating). The 2006 book Rinderpest and Peste des Petits Ruminants, edited by Tom Barrett, Paul-Peirre Pastoret, and William Taylor and published by Elsevier's Academic Press imprint (ISBN-13: 978-0-12-088385-1) is probably the best single-source comprehensive overview for those motivated to hit their local library to learn more.
UPDATE: I would still recommend the dead-tree book I mentioned above. It was the primary reference material used for several sections of this diary. However, the International Food Policy Research Institute published a publicly-available discussion paper. It disagrees with other sources on a few minor topics (how early and for how long the disease was in Egypt), but does a fairly comprehensive job of summarizing the history of the disease, and goes into far more detail about the eradication effort and its economic benefits than I would ever have considered doing.