A Messy Story - The Monster at Our Door: The Global Threat of Avian Flu - page 23

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A Messy Story
An outbreak, like a story, should have a coherent plot. 86
Philip Mortimer
In 1993 Oxford University Press published a collection of essays, edited by Rockefeller University's Steph-
en Morse, on new and reemergent viruses. Unlike most scholarly anthologies, Morse's volume combined
the indisputable authority of the field's leading researchers (including influenza's “emperor” and “pope,”
respectively, Edwin Kilbourne and Robert Webster) with an unusual sense of urgency. Written in the shad-
ow of the AIDS pandemic and the Ebola outbreak in Africa, Emerging Viruses warned that global eco-
nomic and environmental change were speeding the evolution and interspecies transmission of new vir-
uses, some of which might be as deadly as HIV. In his foreword, Richard Krause of the National Institutes
of Health pointed to the new ecologies of disease resulting from globalization. “Microbes thrive in these
'undercurrents of opportunity' that arise through social economic change, changes in human behavior, and
catastrophic events. . . . They may fan a minor outbreak into a widespread epidemic.” 87
One such catastrophic event is Third World urbanization, which is shifting the burden of global poverty
from the countrysides to the slum peripheries of new megacities. Ninety-five percent of future world popu-
lation growth will be in the poor cities of the South, with immense consequences for the ecology of disease.
This concentration of the world population in deprived conditions, more than global population growth per
se, undergirds what William McNeill calls the “Law of the Conservation of Catastrophe.” 88
McNeill is a well-known University of Chicago historian of disease ecology. He writes:
It is obvious that as virus host populations (or potential host populations) increase, there is concom-
itant increase in the probability of major evolutionary changes in virus populations due to increased
opportunities for replication, mutation, recombination, and selection. As the world population of hu-
mans (and of their domestic animals and plants) increase, the probability for new viral disease out-
breaks must inevitably increase as well. AIDS is not the first 'new' virus disease of humans, and it
will not be the last. 89
“From the point of view of a hungry virus,” McNeill writes in another piece, “we offer a magnificent feed-
ing ground with all our billions of human bodies, where, in the very recent past, there were only half as
many people.” 90 (As we shall see later, this same relationship between population density and viral evolu-
tion obviously applies to industrial livestock as well.)
How is McNeill's gloomy principle actually woven into the complex fabric of a human-influenced bio-
sphere? In one of the rare studies that has actually attempted to conceptualize the vast web of intercon-
nection between urbanization, the world economy, and the natural environment, an international scientific
team recently looked at the implications of the soaring bushmeat trade in West Africa. Their 2004 article