Dr. Rita R. Colwell
Director
National Science Foundation
Interagency Meeting on Disease and Homeland Security
National Science Foundation
September 25, 2002
See also slide
presentation.
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please contact
The Office of Legislative and Public Affairs: (703)
292-8070.
Thank you. It's a pleasure to welcome all of you to
NSF, and it's an excellent portent to have expertise
from such a variety of government agencies gathered
in one room. All of us know that our focus today--disease
and homeland security--is more urgent than ever. Today
we will be approaching it from a kaleidoscope of perspectives.
The perspective of each agency represented here is
unique--and each one is critical to creating a complex
and complete picture of disease. Collectively, we
cover the spectrum from medicine to agriculture, from
public health to basic research, from remote sensing
to intelligence analysis, and more. As I wrote in
an op-ed piece in the Baltimore Sun last week, we
need to marshal all this talent to move beyond what
I call "brush-fire biology"--response to short-term
epidemics--and develop a more comprehensive and sustainable
effort.
Forty years ago, Nobelist Sir Frank Macfarland Burnet
wrote, "One can think of the 20th century
as the end of one of the most important social revolutions
in history--the virtual elimination of the infectious
disease as a significant factor in social life."
[Table of most
deadly events]
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This table showing the most deadly events in human
history makes quite the opposite case. Infectious
diseases are responsible for the three most deadly
events--the Spanish Flu, the Black Death of the Middle
Ages, and AIDS. Two of those events took place in
the 20th century, and one of them, AIDS,
is still very much with us.
Our expertise at today's meeting goes beyond human
disease, and I'm very pleased about that. The recent
theft in Michigan of a bacterium causing a serious
respiratory disease in pigs underscores the need for
comprehensive biosecurity in this country and abroad.
We can also look to the past for a sobering perspective
on how disease can decimate crops or livestock or
the environment. How different would the history of
our country--and others--have been if the potato blight
had not led to the starvation of one million Irish
people and forced another two million to migrate to
the United States and elsewhere? Our own history is
inseparable from the fate of our living environment.
As a headline said recently, "The worst bioterrorist
may be nature itself."
Today I hope we can begin to outline the potential
for a new, comprehensive and global infrastructure
to study disease. We need to construct baselines for
disease--to understand their natural dynamics in the
environment--as a prelude to prediction. Here is a
basis for a vision: to make predictions of disease
outbreaks--such as for flu season--the way we now
forecast the weather.
Coordinating among all our agencies is absolutely critical
to a synthetic approach to human, animal and plant
diseases. Certainly, no single agency can provide
an overview; for this, we must all pool resources
and points-of-view. Today's discussions, I hope, will
give each agency's representatives a chance to begin
to see how each piece fits into the whole. The world
of disease is astoundingly complex, and only with
a complex, multiagency perspective can we approach
it.
We also need to envision the possibility of a universal
data-sharing architecture. Let's think about learning
to talk with each other in a mutual vocabulary; for
example, what constitutes an epidemic in agriculture
might be very different from an epidemic defined by
the National Institutes of Health. Specific areas
needing coordination, gaps in our efforts, programs
to fill these gaps, and ways to bridge the gap between
research and development and operations--today's meeting
should provide a basis to begin tackling these challenges.
Our work contributes to homeland security in a fundamental
sense--it's not just about a quick response to today's
threat, or about tomorrow's problem. We need to ground
our perspective not only in the time frame of the
next year, but in the next decade and beyond.
I will now touch upon some themes to help us think
about our multifaceted task, and to illustrate how
fundamental research can contribute to security. This
framework must have a global and interdisciplinary
perspective. It must take full advantage of the cutting-edge
tools that are now helping us to grasp the complexity
of life.
[dust storm
off Africa]
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The global view brings insight on a new scale. Here
is a dust storm, originating over West Africa and
surging out over the Atlantic Ocean. The African dust
carries with it billions of microorganisms--many fungi,
bacteria and viruses, among them pathogens of both
humans and plants, as well as beneficial organisms.
The phenomenon underscores that pathogens do not carry
passports. The global travel of human beings has also
transformed epidemiology, making it critical to consider
transportation issues in our framework.
[life around
undersea vents]
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Microorganisms represent a great unexplored frontier.
Microbial diversity exists even in the most extreme
environments, such as around this undersea vent, and
we have just begun to fathom it. Genomics, for the
first time, offers the possibility to identify "what's
out there."
Even the depths of the sea really are not so remote.
A note from my own research: We have very recently
identified bacterial genes of the genus Vibrio
at hydrothermal vents in the Pacific Ocean. The molecular
evidence suggests that these new Vibrio isolates
share many properties with Vibrio cholerae,
the organism that causes cholera. The most speculative
research unexpectedly links back to human health.
[Lenski: bacterial
and digital evolution]
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Understanding the complexities of evolution in microorganisms
is fundamental to a deeper picture of disease. The
intersection of disciplines brings powerful insights
to bear. Richard Lenski, a biologist at Michigan State,
has joined forces with a computer scientist and a
physicist to study how complexity evolves, using two
kinds of organisms, bacterial and digital. Here, the
two foreground graphs actually show the family tree
of digital organisms--artificial life, evolving over
time. The organisms on the right compete for diversified
resources, and branch out more than the family tree
on the left. In the background are round spots--actually
growing and evolving populations of the bacterium
Esherichia coli, to provide comparison. In
vivo derives insight from in silico.
[Buford Price:
Background: Long duration balloon launch in Antarctica;
optical sizing graph]
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Here's another surprising example of insight at the
intersection of disciplines, again stemming from basic
research, this time in physical science. A high-energy
physicist, Buford Price of the University of California-Berkeley,
developed a filter to study cosmic rays above Antarctica.
The filter is now being turned in a new direction:
to study anthrax.
The team has used the device to show that four species
of Bacillus--the genus of anthrax--cluster
into distinct populations. The team hopes to test
the device in mailrooms.
[two networks
from Newman]
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Mathematics also offers tremendous potential for helping
to track disease, which we are just beginning to exploit.
Mathematical network theory applies to the World Wide
Web, to collaborations among scientists, and of course
to the way diseases spread. Network models are vital
to understanding the character and progression of
an epidemic.
Here, network research by Mark Newman of the Santa
Fe Institute depicts two types of human networks.
If we attempt to apply a strategy to control disease--that
is, to find highly connected people and to treat them--it
works well with the case on the right, but not in
the network on the left. The catch is, however, that
most social networks seem more like the one on the
left. As Newman says, "This suggests that our current
simple strategies for tackling the spread of infection
may not be effective."
[Table of diseases
with environmental links]
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An ecological perspective is also essential to dealing
with the challenge of disease in the 21st
century. This table gives examples of some diseases
that interact with climate. One important climate
pattern, El Nino/Southern Oscillation, has been linked
to outbreaks of malaria, dengue fever, encephalitis,
diarrheal disease and cholera. Environmental change
can nudge pathogens and vectors toward new regions,
creating "emerging diseases" at new locales.
[cholera outbreaks,
SST and SSH]
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My own work traces one of these stories--the case of
cholera. In endemic regions, cholera appears seasonally.
As we now know, environmental, seasonal and climate
factors influence the populations of the larger host
organism for cholera, the copepod.
Cholera epidemics are seasonal. Using remote sensing
imagery, we discovered that, in areas of Bangladesh,
cholera outbreaks occur shortly after sea surface
temperature and sea surface height are at their zenith.
This usually occurs twice a year, in spring and fall.
[cholera in
the Chesapeake Bay]
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In the 1970s, my colleagues and I realized that the
ocean itself is a reservoir for V. cholerae,
much of which might not be culturable from the water,
but it is still present (this slide shows our sampling
sites). In fact, the natural population of cholera
bacteria fluctuates with the seasons in the Chesapeake,
just the way it does in the Bay of Bengal.
[phylogeny
of hantavirus]
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Another excellent example of a disease only understandable
in its environmental context: Hantavirus. Many of
you will be familiar with the story of how the hantavirus
was discovered in the Four Corners area of the United
States. Its carrier turned out to be a deer mouse,
whose population varies with ecological conditions--including
a link with El Nino.
Hantaviruses generally have evolved closely with their
rodent hosts. Looking at this phylogenetic tree, on
the left we see the various viral strains, and on
the right the rodent species that host each one.
[Canyon del
Muerto]
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In New Mexico, Canyon del Muerto, pictured here peppered
with red dots, seems to be a likely place for hantavirus
to "hide" for years between outbreaks. It will be
interesting to learn what role this virus plays in
nature.
[West Nile
Virus maps, showing spread of disease]
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A more recent occurrence in the U.S., of course, is
West Nile Virus. An article in this September's Lancet
points out, "The dramatic appearance of epidemic West
Nile meningoencephalitis in the New York City area
in 1999…is an unsettling reminder of the ability of
viruses to jump continents and hemispheres." We see
here the progressive spread of West Nile virus across
the United States; eventually it is predicted to spread
to Central and South America and to the Caribbean
as well.
This series of maps merely records history, but imagine
if these had been predictive maps--if we had the environmental,
medical and social information, and were able to synthesize
it, to produce predictions of outbreaks of West Nile
and other diseases.
West Nile's appearance in this country carries another
lesson. It appeared in animals four-to-six weeks before
it was found in humans--all the more reason to include
the Department of Agriculture in an effort on disease
and homeland security.
We need a much richer understanding of how organisms
react to environmental change. Today, we simply do
not have the capability to answer ecological questions
on a regional to continental scale, whether involving
invasive species or bioterrorist agents.
In this context, NEON--the planned National Ecological
Observation Network--will be invaluable. I would like
to play you a short video clip that illustrates the
concept of NEON. The video, please.
[1-minute 40 sec. NEON video with soundtrack] video
not available
[Static and
dynamic approaches to public health]
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I think we've seen how NEON will be able to track environmental
change from the microbiological to the continental
scale. Let's move from there to a framework for thinking
more dynamically, and realistically, about infectious
disease (and I thank Mark Wilson of the University
of Michigan for the concept).
The white triangle depicts infectious-disease agent,
host, and environment frozen in time and space. In
this model, we tend to wait for clinical cases to
appear before public health measures are taken.
A more dynamic view--the colored triangle--suggests
the complexity of the real world, with time lags,
feedbacks, and interactions across scales. Such an
approach contradicts the linear, simplistic notion
that we can successfully eradicate a disease from
the face of the planet.
At the same time, as we plot these complex links, and
recognize signals from climate models and incorporate
them into health measures, new opportunities arise
for proactive--rather than reactive--approaches to
public health.
[Ship and Aldo
Leopold quote]
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The prophet of ecology, Aldo Leopold, counseled that
we must "covert our collective knowledge of biotic
materials into a collective wisdom of biotic navigation."
With new tools, with the insights from the intersections
of disciplines, and with a global perspective, we
are launching for the first time on a course to chart
the outlines of our biocomplex world, and that includes
the dynamics of disease. The infrastructure and approaches
developed to understand infectious disease also poise
us to confront the threat of bioterrorism.
With this perspective, I hope we will hear the thoughts
of all today on how we as federal agencies can connect--how
we can apply the results of cutting-edge research
more quickly to national needs; how we can better
coordinate our efforts; and how we can build the needed
infrastructure that will serve to detect and ultimately
predict disease, whether in the realm of public health,
agriculture, or the environment. It should be a truly
interesting day--and I hope it's only the beginning.
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