Preface
There was a little figure plump,
For every little knoll …
Playmates, and holidays, and nuts,
And visions vast and small
Strange that the feet so precious charged
Should reach so small a goal!”
—Emily Dickinson, “Time and Eternity”
In New England, where I grew up, the history of four hundred years of disease and development is written in stone. The landscape is crossed with dry stonewalls, testimony to backbreaking hours spent transforming forests and wilderness into fields and pastures. Old mills, dams, canal locks, and factories—the foundations of industrialization—still dot the landscape. But it is the headstones in churchyards and old family plots that provide perhaps the most direct, human connection to that past.
One such old family cemetery plot was just down the street, near my school bus stop. For years, I occasionally stopped to look at the names and dates engraved on the headstones. The children outnumbered the adults buried in this small plot and I recall several stones for infants who never made it past their first month. By the time I completed elementary school, I was older than most of the occupants of that cemetery plot. Yet, I did not experience the death of a friend or playmate until college. Not only did I survive childhood, but nearly all of my peers did too.
My good fortune is a relatively recent development. In 1880, the date listed on the most recent grave in that plot, twenty-two out of every one hundred infants in the United States died before their first birthday and many more were stricken with serious illness. The survival rates for African-American children were worse.1 The United States was not poor in 1880, not even by today’s standards.2 The country was industrializing, particularly in New England, and the nation experienced strong economic growth in the two decades before the US Civil War. Americans were literate and well fed relative to the citizens of other nations. And yet, US life expectancy at birth had only gotten worse.3
Figure 0.1
Farms Road Cemetery. Photo: Richard Roberts, 2004. Courtesy of the Stamford Historical Society.
The dominant killers of infants and children in the United States in 1880 were bacteria, viruses, parasites, and protozoa that led to infectious diseases, and human responses to those diseases. Terrifying epidemics of smallpox, yellow fever, and typhoid motivated the governments of the United States and modernizing nations in Europe to promote measures like smallpox vaccination and quarantine. But the everyday infectious diseases like pneumonia, measles, dysentery, scarlet fever, and tuberculosis kept coming, waging their unrelenting assault on American children. Effective medicines for those diseases would not be invented for decades. A visit from a doctor or a remedy bought from pharmacy was as likely to harm a child as help.4
The accounts of children’s illnesses and their treatment constitute a significant part of nineteenth-century American women’s writings about motherhood. Each new developmental stage, from feeding to teething to weaning, seemed to bring new risks of infection. Parents could do little but live in constant fear that their children would die, so they had more babies in the hopes that some might live.5 The good health that my siblings, the other neighborhood children, and I enjoyed a hundred years later, living in that same community, must have seemed unthinkable.
By the time I reached college, my concerns with disease and its effects on societies were with the present, not the past. An internship at the New York City Department of Health at the height of the city’s HIV/AIDS crisis demonstrated in real time the consequences of epidemics and human responses to them. That searing experience moved me to forgo lab science after finishing my degree and to devote my career to global health, law, and policy.
I first learned about the great histories of parasites, viruses, and other infectious diseases when my brother Paul returned home from college and announced a career change of his own: he no longer wanted to be an architect. He had just finished William McNeill’s Plagues and Peoples, which tells the story of how encounters with infectious diseases have shaped the course of human history, enabling some conquests while dooming others, changing the fortunes of empires, and determining the religious beliefs and cultures of peoples. The book offered a new way of viewing the world, and it resonated with my brother. That interest evolved into a vocation; my brother became an infectious disease doctor. For his fortieth birthday, I cold-called Professor McNeill, who was then 94 years old and semiretired in Connecticut, and asked if he would sign and dedicate a copy of his book. He kindly agreed, and that first edition sits on my brother’s shelf, inscribed in shaky script: “a book you know well.”
It is easy to be taken with McNeill’s landmark book and the other great histories of infectious disease. They tell fascinating stories about the role of microbes in the Spanish conquest of Latin America, the collapse of feudalism, the invention of the printing press, and the delayed colonization of Africa. These books make for excellent dinner party conversation (at my house at least). It is hard to resist Hans Zinsser’s description, in his 1935 book, Rats, Lice, and History, of infectious disease research as swashbuckling affairs in exotic lands:
Infectious disease is one of the few genuine adventures left in the world. The dragons are all dead and the lance grows rusty in the chimney corner. … About the only sporting proposition that remains unimpaired by the relentless domestication of a once free-living human species is the war against those ferocious little fellow creatures, which lurk in the dark corners and stalk us in the bodies of rats, mice and all kinds of domestic animals; which fly and crawl with the insects, and waylay us in our food and drink and even in our love.6
It was only in writing this book about the ways in which changes in global health are shaping the modern world that I came to think again about the role of infectious diseases in the past. McNeill argued that the impact of infectious diseases on the course of world events goes beyond good tales about the thwarted ambitions of kings and captains, which still holds true today. Understanding the role of plagues and parasites in world affairs still provides key insights into the evolution of the state, the growth and geography of cities, the disparate fortunes of national economies, and the reasons why people migrate. This book tells that story, but it is not about the rise or resurgence of plagues, pestilence, and parasites. It is the story of their decline. This book explores the manner and consequences of that decline, first in New England and the other wealthy, industrialized regions of North America and Europe and eventually in many of the world’s poorest nations. In other words, this book picks up where Plagues and Peoples left off.
Miracles have occurred in the global fight against infectious disease, especially in the last fifteen years. Deaths from malaria and tuberculosis have roughly halved. In 2003, 100,000 people in sub-Saharan Africa with HIV/AIDS were on lifesaving treatment; today, more than 10 million people are. The great killers of children—pneumonia, diarrheal diseases, measles, whooping cough, and diphtheria—are receding. The once fearsome scourges of polio and Guinea worm are on the verge of extinction, where they will join smallpox on the short list of diseases that humankind has successfully eradicated. To be sure, far too many children and adults still die each year from HIV/AIDS, tuberculosis, malaria, and other infectious diseases. The decline in plagues and parasites has not been uninterrupted, and it is not guaranteed to continue. Recent outbreaks of the Ebola and Zika viruses are reminders that the risk of pandemics remains ever present and worthy of our constant vigilance. But just because the war on microbes is far from over should not obscure the fact that we are in the midst of a dramatic change in the lived human experience.
For the first time in recorded history, parasites, viruses, bacteria, and other infectious diseases are not the leading cause of death and disability in any region of the world. Eleven thousand fewer children under the age of five die each day from infectious diseases than did twenty-five years ago. The infant mortality rate in the Central African Republic is the highest in the world, but it is half of what it was in 1960 and roughly a third of what it was in the United States in 1880. People are living longer and fewer mothers are giving birth to many children in the hopes that some might survive.
In the past, declines in infectious diseases and longer, healthier lives were a path to prosperity and inclusion. The economist Robert Gordon has argued that “the historic decline in infant mortality centered in the six-decade period of 1890–1950 is one of the most important single facts in the history of American economic growth.”7 US cities, which had staggered against repeated waves of infection, began to flourish. With the improvement in child survival and declining fertility, the rate of women’s participation in the workforce more than doubled, from 12 percent in 1870 to 26 percent in 1940. Girls’ literacy rates improved, and they attended school in greater numbers, with fewer obligations to assist their mothers in caring for their many siblings. Child mortality and school attendance for African Americans continued to lag behind whites, but also improved dramatically.
The early results of the more recent global declines in infectious diseases and child mortality have not been as good. Longer lives in many countries have not been accompanied by the same economic growth, job opportunities, and better governance that occurred with those changes in today’s wealthy nations. These muted gains are not simply the consequence of hopeless poverty and political instability in the countries where the recent declines in infectious diseases have occurred. China was among the world’s poorest countries and on the cusp of famine and cultural revolution when that country began a dramatic campaign against infectious diseases that set the stage for it to emerge as one of the great global economic powers.
The different outcomes of progress against infectious disease are due, instead, to the different ways progress has occurred and the global moment at which it is now happening. Nearly two-thirds of the gains in life expectancy that have occurred in the United States since 1880 predated the availability of most treatments for infectious diseases.8 Medical innovations and foreign aid are playing a greater role now, which has enabled these more recent reductions in plagues and parasites to occur without the gradual social, political, and public health reforms needed to overcome infectious diseases in the past. This approach has prevented millions of unnecessary deaths, but it has not been a panacea for poorer nations and there have been some unintended consequences. One such consequence is that many poorer nations are experiencing increases in noncommunicable diseases like cancers, heart disease, and diabetes that are three to four times faster than have ever been seen in most wealthy nations. Another consequence is the advent of a new phenomenon in human history: poor world cities. Urban areas in lower-income nations are rapidly growing beyond the bounds of their infrastructure, even without the promise of factory jobs to lure farm hands away from their fields and toward the city lights.
Figure 0.2
Data sources: US Census Bureau, CDC, Proquest.
These unintended consequences are exacerbated by factors that most rich countries did not encounter when reducing their burden of plagues, parasites, and viruses. Climate change and increased hostility to trade and immigration in wealthy nations has left poorer countries less equipped to take advantage of the opportunities that accompany declining rates of infectious diseases, and ill-positioned to cope with the resulting challenges. At the same time, many national governments, philanthropies, and international institutions have been slow to adjust to a world in which infectious disease is no longer the dominant problem it once was. The consequences of these challenges and the failure to address them adequately are worrisome and are reverberating across the world’s economic, political, and security landscape.
In short, our recent progress against infectious diseases is a paradox. The historic health achievements of the past decades are remaking a world that is both worrisome and full of unprecedented opportunities. Whether the peril or promise of progress prevails depends on what we do next. Explaining why this is happening and the challenges that lie ahead is the task of this book.
This paradox in the recent progress against infectious diseases has deep roots and far-reaching implications. As a result, this book is necessarily multidisciplinary, a mix of science, history, and international affairs intended for a broad audience. It draws on my own work, often with coauthors, but also on the ideas and scholarship of many others. That list starts with William McNeill, Hans Zinsser, Paul de Kruif, and other authors of the classic histories of infectious diseases, and also includes subsequent scholars who have benefited from microbiological advances that are improving much of what we know about infectious diseases past and present. The price of genetic sequencing has fallen significantly in recent years and there have been dramatic improvements in the ability of researchers to extract and sequence DNA from once-unpromising sources like medieval teeth, ancient bone fragments, Hungarian mummy tissue, and fossilized gorilla feces.9 These developments have greatly increased researchers’ ability to trace the origin, evolution, and impact of microbes in human history.10
In exploring the role that the decline of infectious diseases plays in urbanization, the evolution of the modern state, economic development, migration, and other areas, this book pulls from diverse sources, including the work of many economists and epidemiologists, historians and health workers. Those on whose research I have relied are cited in the text where possible, and without exception in the endnotes. In some sections, I make my case in numbers, depicted in graphs. In each of those instances, I explain the source of those data and how they contribute to the argument of the book: that the ongoing decline in infectious diseases is as consequential as their rise. And, like those great histories of infectious diseases, this book has some good stories to tell, too.
We are in an era of great and welcome progress in the global fight against infectious disease. That fight must continue and we should continue to invest in it. But we must also recognize that making this progress against plagues and parasites has brought about new and unintended challenges, as important progress often does. For us to seize the opportunities and prosperity that came with health improvements in the past, these emerging challenges must be recognized and overcome. Failing to do so may undermine or reverse hard-fought improvements in health and living standards that have been achieved in recent decades.
This book is not just about the role of plagues in the sweep of history, but the countless lives that were lost, one by one, to those diseases, and the precious opportunities to be gained when those lives are saved in an environment where individuals can take advantage of those opportunities. The aim of this book is to accomplish what William McNeill’s classic book Plagues and Peoples has done: to move its readers to see what is happening in the world differently and to be motivated to do something about it.