Can We Control Disease?
Science's victory over bacteria, viruses, and other microbes is far from assured--and we may be part of the problem.
The Coming Plague: Newly Emerging Diseases in a World Out of Balance
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The first electron micrograph of the Ebola Zaire virus, taken in 1978 by Frederick A. Murphy of the Centers for Disease Control. 160,000x magnification. Image courtesy of Dr. Murphy and Acess Excellence, www.gene.com.
Farrar, Straus & Giroux, $25, Penguin USA, $14.95 (paper)
This brilliant book conveys a grim message: that we may be entering a period of dramatic change in our relationship with infectious disease. Over the course of this century people in wealthy countries have become accustomed to a pattern in which we gradually improve our control of bacteria and viruses. The pace of progress may vary, but the trend has consistently been the same: More illnesses are cured by drugs, food can be kept longer, fewer deaths result from infectious disease, and so on. Laurie Garrett, a science journalist, argues in The Coming Plague that this period of steady progress may be ending--we might have passed the peak already. Even if science continues to advance, this may not translate into progress in our overall control over disease. In the near future human populations may increasingly encounter difficult, even disastrous, interactions with viruses, bacteria, and other microbes. Garrett's book aims to rid the public of what she sees as a dangerous complacency about the future of disease.
Though Garrett wants to alert us to extreme possibilities, she does not claim that disasters are certain or inevitable. The systems in question--the causal webs connecting human activities with fast-evolving populations of microbes--are so complicated that it would be unwise to make definitive predictions. Moreover, the book is intended not just to educate the public but to motivate us to make changes that can help prevent many worst-case possibilities from being realized. The prospects for this intervention stem from her central theme: that diseases emerge from patterns of interaction between the biological properties of bacteria and viruses, on the one hand, and human behavior, both individual and as social, on the other. In dealing with "germs" we are not dealing with biological fixities that will always behave as they have in the past. We are dealing with populations of organisms which will change rapidly in response to both our deliberate and inadvertent actions. Our present challenge is to anticipate and plan for these changes, and thereby stay one step ahead.
The Coming Plague has come to occupy a unique place in the book market. How many 750-page books, swarming with references to scientific literature and dense with intricate descriptions of micro-organisms, find themselves in best-seller lists and chain bookstores? Other "emerging disease" books have appeared on these shelves as well, including some sizable volumes, but Garrett's is the intellectual heavyweight of the collection. Despite its length, I found it hard to put the book down. Garrett mixes into the biology some remarkable human stories, including stories of true heroism. These are not scientific "heroes" in just the ordinary sense--tenacious defenders of unpopular views or selfless researchers dedicated to their work--but people prepared to fly at short notice into some of the poorest and most unstable parts of the world to track down, with primitive equipment, an unknown microbe causing hundreds of gruesome deaths.
These stories, and Garrett's clear and attractive style, make the book consistently readable despite the mass of facts. The book's structure is not perfect, however. It would have benefited from the addition of a single, organized discussion of the basic biology of bacteria, viruses, and other disease-causing micro-organisms, as well as an outline of the basics of human immune response mechanisms. Information of this type can be found in the book, but it is scattered throughout and incomplete. Garrett also includes 100 pages of notes and references, but neither a select guide to further reading nor a glossary of technical terms. Perhaps Garrett (or her editors) thought that adding these sections would have made the book look too much like a textbook. But without them, non-specialist readers may sometimes be overwhelmed. More generally, Garrett sometimes barrages the reader with unnecessary detail. The chapter on the emergence of antibiotic-resistant strains of bacteria is filled with mesmerizing chants: a mutant strain of microbe is resistant to "ampicillin, carbenicillin, streptomycin, trimethoprim, sulfamethoxazole, sulfasoxazole, and tetracycline." Most of us do not need such detail.1Despite these shortcomings, The Coming Plague is a superb, constantly fascinating book, and a tremendous achievement.
In any large-scale and ambitious work of this type, details of the discussion can be contested by specialists--I will discuss one particular example later on. There is also evident disagreement about the overall direction in which the facts point. John Postgate's Microbes and Men is an up-to-date and widely-used survey that, in contrast to Garrett's book, displays a low-key optimism about the future of antibiotics. "One can be fairly confident," Postgate asserts, "that more antibiotic-resistant strains [of bacteria] will develop but that these will be kept in bounds by the discovery of new antibiotics, or the deliberate modification of existing ones."2 Garrett sees no reason at all to be confident about this. Being a non-specialist in this area, I cannot adjudicate their disagreement. So in this review I will mostly accept Garrett's factual claims about the history and biology of various diseases at face value, and then consider--as I think we all must--their potentially horrifying implications.
Garrett's story focuses on the period between the 1950s and the present day, although there are constant comparisons with the distant past as well. Two contrasting cases are useful for setting the stage. The first is a success story--the eradication of smallpox. In 1958, at the Soviet Union's prompting, an organized international effort to eliminate smallpox was initiated. Smallpox, an ancient and deadly viral disease, was then killing two million people each year. But a vaccine existed, and in the following years teams organized by the World Health Organization roamed the world, first treating and vaccinating, and then hunting down the shrinking number of cases. In 1977, after a great deal of difficult and patient work, the last naturally occurring case of smallpox was found and cured. Except for samples in two high-security laboratories, the virus is now gone from the earth.
Consider, in contrast, the case of malaria. In the late 1950s--a period of widespread optimism about the prospects for definitively eradicating a great range of human diseases--public health specialists held out high hopes for eliminating malaria, an old and enormously destructive disease caused by mosquito-borne parasites. There was a burst of effort, aided by US funding, but in 1963 the funds dried up and, for a variety of reasons, the situation began to deteriorate. Today's malaria problem is, in many regions, far worse than it was fifty years ago. The disease itself is often more serious than it used to be, as many current strains of the parasites are able to tolerate both old and new drugs. By 1990 malaria was killing up to a million children each year in Africa alone.
These two cases give a sense of how well, and how badly, things can go. Should we, then, expect more smallpoxes or more malarias? Garrett develops her view through a series of detailed discussions of particular diseases. I will divide these cases into two classes. The first group contains new, exotic, and terrifying viral diseases such as Ebola, Lassa, Marburg and some forms of hantavirus disease. Many cause forms of "hemorrhagic fever," in which the virus produces a variety of gruesome symptoms including widespread bleeding and breakdown in vessels carrying and separating fluids throughout the body. Outbreaks of these diseases, of the type that attracts international attention, began in the 1960s and 1970s. Some are specific, at present, to parts of Africa (or in one case, South America). Others, like hanta, are found in different varieties throughout the world. The threat posed by these exotic diseases, all deadly and highly infectious, is dramatic and easy to grasp. The name "Ebola" is fast becoming a familiar part of contemporary English, with connotations of bio-apocalypse and the end of humanity.
The diseases in the second category of Garrett's cases are more familiar. These are all old problems, such as tuberculosis and malaria, and even wholly unexotic bacteria like staphylococcus. It is here that the argument of the book is made most forcefully. When we contemplate a killer such as Ebola, it is hard not to shrug or throw up one's hands. If Ebola became widely established though the world, especially if it mutated to a form that was easily transmitted by air--here we enter the realm of Crichton's Andromeda Strain. It is as though human history had collided with something from a place far outside it. But we cannot think this way about tuberculosis.
Tuberculosis, like malaria, is an old disease now making a comeback. It is caused by a slow-growing bacterium that does not cause significant harm to the majority of people it infects. The disease has long been associated with poverty, and people with weakened immune systems are especially vulnerable. By the 1960s TB was a rare disease in the United States, and it struck mostly older people. But through the 1970s and then the 1980s it gradually shifted and began to reappear in younger people, especially African-Americans and the poor. With the rise of homelessness in the cities it became more firmly established, and once HIV emerged TB began to really take off.
The strains of TB prevalent in the 1960s were easily treated with antibiotics. The strains in US cities now are a very different matter--many of them are resistant to a large range of drugs. Moreover, Garrett argues, the present situation is ideal for the further evolution of drug-resistant strains. Here, as is true generally, if antibiotic treatment is not careful and thorough, the population of bacteria inside an individual can evolve, by various kinds of mutation and natural selection, into forms that are increasingly difficult to treat. Because American TB patients tend to be poor, homeless, drug-addicted, or HIV-positive, treatment is often very sporadic, providing the bacterium with ample opportunity to adapt and evolve into more dangerous and tenacious forms.
The development of antibiotics through the middle decades of the century did not just create conditions for the further evolution of the TB bacterium; the success of these drugs also led to the scaling-down of TB research and a decline in the number of people being trained to deal with it. Consequently, when dangerous new strains of TB emerged in the cities during the early 1990s, the medical establishment was poorly prepared to deal with them.
So we do not need to think in terms of an alien "Andromeda Strain" killer to see the threat ahead; the neglect of public health and misuse of antibiotics and other drugs are helping to create more and more formidable enemies.
Having a very short time between generations, bacteria can evolve much faster than we can, and as more is learned about bacterial metabolism and genetics, researchers are amazed at the diversity of the tricks bacteria use to adapt to our efforts to destroy them. Bacteria, unlike us, can transfer among themselves packages of genetic material (plasmids) that confer resistance to various drugs; they "scavenge" for useful bits of DNA that float around the world being picked up and thrown out by other microbes. Bacteria will constantly evolve, whatever we do. The problem is to avoid situations that encourage their evolution into ever more destructive forms. When antibiotics are prescribed without good reason and without a commitment to ensuring that patients take their full courses, situations are created in which unwanted bacterial evolution is made more likely.
The problem of dangerous antibiotic use is by no means confined to poor and homeless people with TB. The desire to maintain good relations with patients leads to doctors over-prescribing these drugs, and their side-effects tempt patients of all kinds to stop taking the pills once they feel better. There will perhaps always be some tensions associated with the rational use of antibiotics--given the nature of bacteria, the drugs will tend to be more effective the less often they are used. But this does not excuse what amounts to the squandering of valuable and hard-won resources.
I divided Garrett's cases into the new and exotic (like Ebola) and the old and familiar (like TB). But in a class of its own is AIDS, to which Garrett devotes a 100-page chapter. Her discussion includes a fascinating account of the maze of possible evolutionary connections between the different strains of HIV and similar viruses found in various African monkeys.
HIV comes in a range of forms. One basic distinction is between HIV-1 and HIV-2. The general, worldwide AIDS epidemic is a consequence of HIV-1. Within HIV-1 eight branches are distinguished, and these tend to be specific to different parts of the world. In some places--Thailand in particular--it is possible to track the course of several separate HIV epidemics, with different strains spreading in different parts of the population. HIV-2 is found mostly in Africa (although HIV-1 is found there as well), and is thought to be less lethal.
The exact family tree and causal chains connecting these strains to each other and to various monkey viruses (SIVs) are topics of ongoing debate. Important messages appear among the maze of connections and conjectures. It is initially startling that monkey viruses are apparently inserted among the evolutionary relationships between HIV strains. In particular, HIV-2 is much closer to a monkey virus than it is to HIV-1. The class of HIV viruses affecting humans is not a single evolutionary unit, or "monophyletic" grouping, and there may have been a complicated back-and-forth exchange of these viruses between humans and monkeys over time. Some believe that HIV-1 was present in humans in Africa for a long time prior to the epidemic, causing at worst only small-scale problems.
The upshot is that the emergence of HIV in the human population at the end of the 1970s was not an instantaneous, extraordinary biological event. These viruses have had some relationship with humans for a longer period. The change in this relationship, Garrett says, appears to have been a consequence of a complex variety of factors--key social and behavioral changes throughout the world, in combination with particular political disruptions in central Africa during the 1970s, and (perhaps) in concert with an evolutionary divergence of HIV-1 strains around 1975. By means of this web of events, an existing family of microbes came into a new relationship with human activity, with disastrous consequences.
A New Paradigm
What general lessons do we learn from such cases? Garrett claims that they indicate the need for a "new paradigm in the way people think about disease." That paradigm appears to have two main features. First, we must better appreciate the complexity of the relationships between microbes, larger ecological systems, and human social organization and behavior. Second, we must stop assuming that we will keep getting better at controlling infectious disease.
Though Garrett constantly stresses the complexity of disease, she does not argue that we can never isolate the key causal factors in complex systems. Her discussion often shows the opposite: a medium-sized list of factors appears repeatedly. The factors are very heterogeneous; they includes things that lie beyond our control and things that we can do plenty to change.
A variety of demographic factors are causally important. Some diseases require for their survival a "critical mass" of connected humans. Patterns of behavior--especially sexual behavior--have enormous and obvious impact, as do patterns of travel and trade. Wars and various kinds of civil unrest create special opportunities for particular diseases. Typhus, which is carried by lice, has a 500-year history of interaction with military affairs. Epidemics of cholera arise rapidly among communities of refugees.
Although some diseases, including tuberculosis and AIDS, have the capacity to persist within human communities without interacting with other animal species, many diseases--malaria and bubonic plague among them--are passed between humans via insects. Ecological changes, both large-scale and very subtle, affect populations of key insects in ways that have profound effects on human disease. The unremarkable displacement of one mosquito species by another in a particular area can rapidly bring yellow fever or malaria in its wake. Similar consequences may follow from changes in the local numbers of other mammals such as cattle (which the mosquitoes may prefer to humans) or changes in the types of water left standing (in which mosquitoes lay eggs).
Garrett stresses that such changes in animal populations are not independent of human behavior. The development of intensified forms of agriculture--especially of the type recently introduced in (and sometimes imposed on) many developing countries--often reduces the local diversity of insect species. Some populations go way up and others go way down. Sometimes one of the populations that increases will harbor a virus deadly to humans.
When the connections between people and disease go via complicated multi-species chains, and hence are affected by all the huge range of factors that affect ecological systems, prediction and control will always be difficult. But some of the factors are much more predictable--the consequences of poverty, crowding, and the over-use of antibiotics. A sad element in several of Garrett's stories is the role played by well-intentioned half-measures. When hospitals are set up in poor countries but not properly restocked, needles and other instruments tend to be used over and over again without adequate sterilization. In the famous outbreak of Ebola in Yambuku, Zaire, in 1976, a mission hospital acted as a deadly "amplifier" of the epidemic for this reason. The conclusion to be drawn is the same as that in the discussion of antibiotics. Needles and antibiotics are both essential, but their use and availability must be properly planned and not left to chance. The continued ban on needle-exchange programs for drug addicts in the United States is a clear instance of this bad planning.
As she traces her way along these causal webs, Garrett constantly stresses their complexity. She also claims that our present situation is uniquely bad in some respects. World-wide travel is now fast and widespread; someone can get onto a plane in Nigeria feeling perfectly healthy but arrive in an American airport sick with Lassa fever or another highly infectious disease. Brutal local wars are generating millions of refugees--crowded, undernourished groups of people with suppressed immune systems and poor access to health care. AIDS is overwhelming public health efforts--along with individual immune systems and much of the rest of the economy--in many African countries. And AIDS has not yet begun to exact its inevitable toll in Southeast Asia. The overall picture, as Garrett sees it, might be described as one of global connectedness but local chaos.
As she develops this case, Garrett sometimes focuses on one side of a story that also has other mitigating aspects. In Garrett's arguments, fast global travel consistently appears as a bad thing, epidemiologically speaking: Whatever arises in one part of the world can spread rapidly to the rest. There is no denying this role, but other writers on disease discuss another aspect of travel as well. When a group of people is constantly connected, through immediate proximity or frequent travel, and almost everyone is exposed to a given microbe at an early age, there is a chance for the disease to settle into the non-destructive pattern characteristic of familiar childhood diseases.
Measles, for example, is not a dangerous disease to a population continually exposed to it, but when it hits an isolated group for the first time or only at irregular intervals, it can cause enormous destruction. In Plagues and Peoples, William McNeill argues that a key advantage of European societies over others during the period from about 1500 to 1800 was that the European communities had, through trade, travel and population density, formed a single connected pool in which diseases like measles and smallpox circulated constantly in non-destructive patterns.3 When the microbes roaming this system contacted a formerly isolated group, like Native Americans or Pacific Islanders, these diseases caused enormous damage. So patterns of travel clearly play a very complex role, and Garrett sometimes focuses very much on one side of the story.
Similarly, Garrett is prepared to choose sides on some open scientific questions, favoring views that fit with her focus on complexity and the consequences of human behavior. Her discussion of syphilis is an example.
Syphilis seemed to emerge suddenly in the 15th century, but not because the bacterium responsible for it, Treponema pallidum, first appeared then. The bacterium itself is very old, and had long been in contact with humans as the cause for certain skin diseases, including yaws, which mostly affects children and is not serious. But suddenly in the 15th century Treponema infection became a widespread and very destructive sexually transmitted disease. According to Garrett and the research she discusses, the likely cause for this sudden switch was a set of human factors--the development of cities and an increase in multi-partner sexual behavior. The same Treponema bacteria acquired a new way of being passed among humans and became responsible for a new set of symptoms. The behavioral changes that made this possible may have been partly due to a breakdown of sexual codes and constraints after the devastation of the Black Death in the 14th century. The massive effects
of the Black Death were largely due, in turn, to the density and habits of
urban populations. The upshot of all this was a new niche for Treponema,
and from that point to the present day syphilis has been a constant and unwelcome
companion to human sexual behavior.
On Garrett's telling, then, a single biological entity--Treponema pallidum--produces
a variety of diseases as a consequence of the variety of relationships it
can have with humans. (A simpler example is found in the case of plague. Bubonic
plague and pneumonic plague are caused by the same type of bacteria, Yersinia
pestis, but the pneumonic, airborne form of the disease is both deadlier
and more transmissible than the flea-carried bubonic form.) If this view of
syphilis is right, it makes a good case for a complex, interactionist view
of disease. It warns us against assuming that differences between diseases
should all be explained in the same way--in terms of the genetics of the microbes
in question, for example.
But Garrett has chosen sides here. The article on syphilis in the Cambridge
World History of Human Disease, for example, still recognizes two rival
theories on this matter. Garrett favors the "unitarian" view of E.H. Hudson,
whereby one type of bacteria is involved in four diseases: venereal syphilis,
yaws, pinta, and endemic syphilis. The same microbe interacts with humans
in four different ways in different conditions. The rival "nonunitarian" view
holds that the different diseases are caused by slight genetic differences
between the strains. This view associates separate species (or, in some cases,
subspecies) of Treponema with the four different diseases. The nonunitarian
view holds that the successive changes in how Treponema interacts with
humans were due to distinct subtle mutations. The nonunitarian view illustrates
a simpler and more familiar type of biological causation--a genetic change
produces a different microbe, which in turn produces a new disease. The debate
between these two views of syphilis (along with much more about the history
of the disease) remains unresolved.4
The nonunitarian view is still consistent with an emphasis on the consequences
of behavior--it is one thing for a mutation to appear, another thing for it
to flourish. But the unitarian view makes Garrett's case especially well,
and she exhibits a clear preference for it (at least for the syphilis/yaws
relationship) despite the ongoing controversies. I do not intend this as a
major criticism of the book, however. Garrett is meticulous in citing scientific
support for her claims, and her core message about the dangers of our present
situation--though contestable--is buttressed by a mass of evidence.
Progress and Balance
The second pivotal idea in Garrett's new paradigm is that we should not think
of progress as a natural or inevitable feature of our interaction with microbes.
In rejecting a complacent assumption of progress, Garrett joins a large recent
tradition of work criticizing the tendency to see progress as ubiquitous.
In biology, Stephen Jay Gould has been an acute and outspoken critic of progressivist
assumptions (see any of his collections of essays, or his Wonderful Life).5
And Thomas Kuhn's work in the history and philosophy of science famously questioned
some traditional assumptions about the progressive nature of scientific change.6Garrett's
argument has a similar critical thrust.
Her argument is not simply that we should stop assuming steady improvements
in our control of microbes. Most people, after all, would agree that germs
could get the better of us: society could break down, or science could be
abandoned. Only a very extreme progressivist--perhaps Herbert Spencer--could
see progress as literally inevitable. Garrett's message is that even if science
continues to flourish and progress in all the relevant areas, and even if
the basic structure of western society remains intact, this need not translate
into effective control over disease. Given the nature of human interaction,
if the application of science is short-sighted and if political and economic
change takes the wrong course in key communities, knowledge will not save
Garrett makes a strong case against progressivist assumptions. She is less
critical, however, in her treatment of ideas of balance and equilibrium. The
subtitle of the book is "Newly Emerging Diseases in a World Out of Balance,"
and she uses the word "imbalance" to describe the overall situation of the
earth and our relation to it. The biologist Richard Lewontin and others have
recently argued that concepts of balance and equilibrium--particularly the
idea of a "balance of nature"--have assumed a role in 20th-century biological
thinking that is similar to the role occupied by ideas of progress in the
19th century.7 Where an earlier generation looked everywhere
for progress and regarded it as normal and proper, more recent writers think
of balance and equilibrium as the natural state of affairs. Though equilibrium
has become central to a great deal of biological thinking, Lewontin argues
that the popularity of these concepts lacks scientific justification: the
idea of a state of balance is often overextended, and the "balance of nature"
is a myth.
Whether or not Lewontin's critique is right in general, it should prompt
us to inquire closely the use of ideas of balance in specific parts of contemporary
biology. In understanding interactions between microbes and humans, there
are apparently some phenomena that are accurately described in terms of balance--for
example, our relationship to the populations of bacteria in our own intestines.
But it is a large step from such cases to the idea that our general relationship
to the microbial world as a whole was, or should be, one of "balance." And
it is another step again to say that we should now seek to restore the lost
Although Garrett gives ideas of balance an important place in her official
statements, she does not really harp on the idea. This is just as well, for
most of her stories do not support a view of human/microbe interaction in
which a concept of balance is central. Along with some unhelpful talk about
"linear" versus "nonlinear" perspectives, the talk of balance is more a feature
of her summaries. The overall message told by her carefully-developed examples
is one in which balance, progress, regress, chaos, cycles--and whatever else
we might find--are all to be understood as contingent products of very complicated
systems. No particular type of outcome is the natural state or default expectation.
The book is not really about restoring a lost balance; it is about changes
and permanences of many different kinds, which combine and recombine to produce
our overall relationship with TB, HIV, and so on. Equilibrium is one possible
outcome among many, and we should not think in terms of an ancestral golden
age of balance in our dealings with microbes.
A few paragraphs back I cited Gould's Wonderful Life as a critical
discussion of progressivist ideas. In that book Gould advocates a picture
of the biological world centered upon the contingency, quirkiness, and unpredictability
of natural processes. For Gould there is wonder in this view of life. Garrett's
The Coming Plague is a grim companion to Gould's book. It focuses,
like his book, on highly contingent processes and urges us to resist the idea
that some global progressive principle lurks behind the hubbub of interaction.
Blame and Response
Though Garrett stresses complexity, she is entirely prepared to assign blame.
And she assigns it widely: to various religious authorities and ideas, careerism
and bureaucracy at the United Nations and World Health Organization, Ronald
Reagan, racism, sexism, despots in Africa and elsewhere, antibiotic use in
American factory farming, government corruption, well-intentioned but short-sighted
aid projects, homophobic moralizers, budget-cutters who target public health,
greedy drug companies, politically-correct fumbling and denial, World Bank
policies encouraging export-oriented agriculture in the developing world,
multinational corporations. Garrett also outlines positive proposals for improving
both our actions and our ways of thinking about disease. In the final chapter
she calls for both a theoretical and practical focus on disease "amplifiers"--habits,
institutions, artifacts, and patterns of life that can transform a localized
outbreak of disease into a large-scale public health problem. At the top of
her list she places sex, followed by re-used hypodermic needles, and then
a host of lesser but still important factors--among them non-chlorinated water,
air-conditioning, deforestation, and urban crowding.
Garrett also argues that confronting the threat of disease more rationally
requires that we confront it less individualistically. We find extreme individualism
in the current organization of American health care, where the market model
prevails in the organization of medicine and there is no universal system
of health insurance. Each individual is expected to shop the available health-care
products as well as he or she can. But maintaining one's health is not so
private a matter. Competitive market pressures might hone the power of the
drugs and techniques available to the well-insured, but the same market-based
system simultaneously fills the country with people who have only very precarious
access to health care. The state of health of the well-insured, however, is
not independent of the state of health of the uninsured. When large segments
of the population are poor and uneducated and live in crowded and unhealthy
conditions, such diseases as TB can persist in a community which would otherwise
deny them a foothold. The insured may have, for a time, a battery of drugs
that keep the microbes at bay. But these conditions are breeding grounds for
ever more dangerous forms of microbes. The wealthy and insured cannot assume
that the drug companies will always stay a step or two ahead of the germs.
AIDS, the great pandemic of present times, is not a model for every problem
that might come along. If a person is educated about risk behaviors, is not
subject to sexual coercion, and lives in a society with good medical practices
and a blood supply secured against contamination, he or she can be fairly
sure of avoiding HIV infection. But a new airborne or insect-borne virus would
be a very different matter. So would a strain of toxin-producing bacteria
that found some way to evade the last card in our deck of antibiotics, and
which took up residence in hospitals across the country.
There are many good arguments for instituting a system of universal health
coverage (a "single-payer" system) in the United States. Some arguments appeal
to a sense of fairness, but the argument I focus on here is based as much
in self-interest as in any considerations of justice. A private and market-based
system, which tolerates massive inequalities in the quality of health care
available to different people, is not the way to work towards public health,
and the wealthy and insured part of the population has as much to fear from
future plagues as the poor.
Garrett does not stress this argument about the inadequacy of market-based
health care systems, but it appears to me a clear consequence of her overall
view. Garrett's own general conclusions are more global in scope. She stresses
the need for well-funded surveillance of public health across the world, especially
in key places such as Africa, South America, and Southeast Asia. If money
is invested in the early detection and containment of local epidemics, more
will be saved in the long run. Garrett also stresses the connection between
public health and environmental issues--especially the consequences of large-scale
projects like deforestation. Garrett ends her concluding chapter, "Searching
for Solutions," by focusing on these issues of ecology. At the very end of
this chapter she unfortunately strays toward the utopian; our only hope for
staying ahead of the microbes is to "learn to live in a rational global village."
If this really is necessary, then we are indeed in bad shape. But the rest
of the book belies this final message; there is much that can be done from
this side of utopia that will improve our chances.
An earlier writer, quoted by Garrett, looked around at antibiotic-resistant
bacteria and said: "These are organisms that are part of our endgame."8
Though parts of Garrett's book convey a similar sense of doom, her overall
message is not fatalistic. Disasters of many kinds might be averted through
intelligent reassessment and planning in public health, ecology, and economics.
Given the fallibility of projections about systems of this complexity, it
must also be possible for us to continue along our present shortsighted path
and evade catastrophe by sheer luck.
The book does claim that, given our understanding of the basic biology of
the microbial world and its interaction with human activity, and given the
lessons of the recent past, we must at least be prepared for real trouble
in the years ahead. These years may include episodes in which exotic viruses
sweep around the world leaving trails of destruction behind them; they may
also include a gradual, subtle erosion of the ability of hospitals in all
countries to cure people's ailments while protecting them from new infections
picked up during treatment.
Garrett's message includes some utopianism but it also outlines some clear
and useful principles for maximizing our chances. Again,, the one I would
single out and stress as paramount is the need for medical systems to be planned
and organized around the goal of public health, not just the curing of disease
in individuals. Whatever one believes about the respective roles of government
and free markets within economic life as a whole, in a technologically advanced
and overpopulated era the supply of health care is not something that can
be treated like the supply of tennis balls. At the national level, this requires
an organized system of universal health care.
The Coming Plague was published just two years ago but the situation
has not remained static since that time. Garrett's book appeared too early
to catch the "mad cow disease" scare which hit the British beef industry in
March 1996. Mad cow disease is caused by a "prion," a mysterious agent that
seems to work somewhat like a virus while having none of the usual genetic
apparatus (DNA and/or RNA) found in other microbes. The prions associated
with mad cow disease have now been linked to lethal brain disorders in humans.
Hantavirus, which causes hemorrhagic fever, has now made its way via deer
mice to many areas in California, including Santa Barbara and the Lake Tahoe
area.9 Late last summer parts of Rhode Island and Massachusetts
experienced considerable anxiety over the discovery of mosquitoes infected
with Eastern Equine Encephalitis virus. Amid smaller amounts of publicity,
increasing numbers of people are finding out that they have been infected
with hepatitis C, a very dangerous form of hepatitis whose pattern of transmission
is not well understood. And on the day that I write these words, a tiny entry
on the front page of the Wall Street Journal notes the small but rising
death toll associated with an Ebola outbreak in Gabon, West Africa.
1 For a brief discussion of the biology of bacteria and
viruses to complement Garrett's book, see John Postgate's engaging Microbes
and Men, 3rd ed. (Cambridge: Cam
bridge University Press, 1992).
2 Postgate, Microbes and Men, pp. 270-71.
3 William McNeill, Plagues and Peoples (New York:
Anchor Books, 1975).
4 Part of the difficulty here arises from the fact that
the standard criterion for the identification of species--the capacity to
interbreed--does not apply to bacteria. So classifications of bacteria are
more arbitrary. For this alternative discussion of syphilis see J.Arrizabalaga,
"Syphilis" in the Cambridge World History of Human Disease, ed. K.F.
Kiple (Cambridge: Cambridge University Press, 1993) especially pp. 1026-27.
Another example of Garrett's choosing sides is her favorable discussion of
the controversial topic of "adaptive" or "Cairnsian" mutation in bacteria.
5 Stephen Jay Gould, Wonderful Life: Burgess Shale and
the Nature of History (New York: Norton, 1989).
6 See Thomas Kuhn, The Structure of Scientific Revolutions
(Chicago: University of Chicago Press, 1970).
7 See Richard Lewontin, Biology and Ideology (New
York: Harper, 1991).
8 Marc Lapp, Germs that Won't Die (Garden City:
Doubleday, 1982); cited by Garrett, p. 437.
9 San Francisco Chronicle, November 26, 1995.