The Interface Between Human
and Veterinary Public Health
Emerging Zoonotic Disease Summit
Gainesville, Florida
August 23, 2005
Lonnie J. King
Director, Office of Strategy and Innovation, CDC
Dean, CVM, Michigan State University
Historical Epidemiological Transitions
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Paleolithic Age
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Hunters and gatherers
Nomadic
Small populations
Parasitic infections
Historical Epidemiologic Transitions
– 1st Transition
 10,000 years ago
 New social order due to
agriculture
 Zoonoses through animal
domestication
 Increases in infectious
diseases
 Epidemics in non-immune
populations
Deadly Gifts
Human Diseases
Animal Origin
Measles
Rinderpest of
cattle
TB
M. bovis of cattle
Smallpox
Cowpox
Influenza
Pigs and Ducks
Pertussis
Pigs and Dogs
Malaria
Birds
Guns, Germs and Steel  J. Diamond
Historical Epidemiologic Transitions
– 2nd Transition
 Coincided with mid-19th
century Industrial Revolution
 Decreases in infectious
disease mortality
 Increasing life expectancy
 Improved nutrition
 Antibiotics
 “Diseases of Civilization” – cancer,
diabetes, cardiovascular diseases
 Environmental problems
 Chronic diseases
Historical Epidemiologic Transitions
– 3rd Transition
 Last 25 years
 Emerging infectious diseases globally
 New diseases and increases in mortality; first since
19th century
 Re-emergence
 Antimicrobial resistance
 75 percent of diseases are zoonotic
 Anthropogenic factors of emergence;
the microbial “perfect storm”
“The Perfect Storm”
 Sebastian Junger

an ocean tempest due to a rare combination of
factors and circumstances that might occur
every century
MICROBIAL THREATS
TO HEALTH
EMERGENCE, DETECTION,
AND RESPONSE
INSTITUTE OF MEDICINE
OF THE NATIONAL ACADEMIES
National Academy Press
Washington, DC
2003
The “Microbial” Perfect Storm
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Due to special combinations and circumstances
Relatively common occurrence
Doesn’t dissipate, but may perpetuate or
accelerate
Convergence model
WHO Map on World –
Emerging Diseases
Convergence Model
Genetic and
Biological
Factors
Physical
Environmental
Factors
Microbe
Human
Social, Political
and Economic
Factors
Ecological
Factors
Convergence Model (Microbial Threats to Health – IOM/NAS, 2003)
Factors in Emergence
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Microbial adaptation and change
Host susceptibility to infection
Climate and weather
Changing ecosystems
Economic development and land use
Human demographics and behavior
Technology and industry
Factors in Emergence
continued
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International travel and commerce
Breakdown of public health measures
Poverty and social inequality
War and famine
Lack of political will
Intent to harm
Multihost Pathogens
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60% of all human pathogens are zoonotic
80% of animal pathogens
Ecological generalists
New Dynamic
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Emerging diseases – 70% zoonotic
New zoonoses
Food safety
Antimicrobial resistance
Agents of bio- and agro-terrorism – 80% zoonotic
Global trade and movements
Rapidly Increasing Human
Population
•
6.1 Billion people
in 2000
•
~9.4 to 11.2 Billion in 2050
Source: United Nations, World Population Prospects, The
1998 Revision; and estimates by the Population Reference
Bureau.
Rapidly Increasing Urbanization
•
2000
-
•
47% world population
living in urban areas
2030
-
60% world population
living in urban areas
The Divided World of 2025 –
8.4 Billion People
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World 1
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World 2
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World 3
Advanced nations
(Advances in medicine and food)
Middle class
(Livestock Revolution)
People in destitution and poverty
(Sources of traditional pathogens)
El Nino
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Leptospirosis
Hantavirus
Rift Valley fever
Vectors of Disease
Global Warming
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Shifting and enlarging the incidence and
distribution of disease
Malaria zone 45% of population to 60%
Habitat change and disruption via weather
changes
Global Warming Effects on Malaria
Ecosystem
Waterborne Zoonoses
Humans
Animals
Waterborne
Disease
Microbial
Pathogens
Water Environment
Waterborne Zoonoses –
Global Threat
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4 billion cases of diarrhea per year
2-3 million deaths
Poorly reported
Zoonotic portion is significant
Endemic and epidemic
1.1 billion people with unreliable water supply
Waterborne Zoonoses Pathogens
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Cryptosporidium
Giardia
E. Coli 0157:H7
Salmonella
Leptospiria
Toxoplasma
Campylobacter
Entamoeba
Ascarsis
Viruses and Prions? SARS?
Concentrated Animal Feeding
Operations (CAFOs)
Their Impact on Food Safety and
Healthy Environments
Foodborne Infections
•
Worldwide

•
> 2 million people die from diarrhea caused by
contaminated food and water each year
U.S.

~ 76 million persons experience foodborne illnesses (1
in 4 people)
-
~325,000 hospitalizations
-
~5,000 deaths
Most Common Foodborne Pathogens
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Campylobacter
Salmonella
E. coli 0157:H7
Yersinia
Listeria
Cryptosporidium
Cyclospora
Norwalk-like viruses
Livestock 2020 –
The Next Food Revolution
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Global increase and demand for protein and food
of animal origin
Shift from poverty of 1-2 billion people to middle
class
“Westernization” of Asia and Latin America
Concerns with sustainability
Increases in emerging zoonoses through the
concentration of people and animals
By 2020, There will be 1 Billion
People Over the Age of 60
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30% of US population are baby boomers
Immuno-compromised population
Movement and Interactions
of People and Commerce
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Distance and speed of travel increased 1000 fold
since 1800
1.4 billion air travelers/year
50 million foreign visitors, to US year through,
102 sites
Antibiotic resistance
Global trade of food, animals and plants
The Coming Plague
Today’s mingling of people, animals and microbes
in new environments has no historical precedent.
-”We await the coming plague”
- Laurie Garrett
Remote Sites
Pathogen Pollution
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Human and domestic animal populations
Free-living wild animals
Example: global decline in amphibian populations
due to chytridiomycosis
Concern with adverse effects on biodiversity
Chytridiomycosis
Virus Carriers
Fruit bats
Flying Foxes
Nipah Virus
Malaysian Pig Farms
Emerging Infectious
Diseases
Encroachment
Introduction
“Spill over” &
“Spill back”
Agricultural
Intensification
Translocation
Wildlife EID
Domestic
Animal EID
Dasazak P. et.al.
Science 2000 287:443
Human
encroachment
Ex situ contact
Ecological
manipulation
Human EID
Technology and
Industry
Global travel
Urbanization
Biomedical
manipulation
Spill Over and Spill Back
What’s Next?
Human Monkeypox Cases
Marshfield Clinic and MCW
Matt Kuehnert
Exotic Pets
SARS
Maintenance Host
SARS Airport Screening
The Lessons of SARS
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The need for multinational collaboration
Public alarm can lead to huge economic impact $80 billion
Weaknesses in public health infrastructures
Consequences of poor reporting –disincentives
A true zoonosis: more to come
Constant threat due to Emerging Infectious
Diseases in less developed countries
H5N1 Avian Influenza
Pandemic Influenza
The Next Influenza
Pandemic
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Not if, but when
1918-1919 Experience:
20 million deaths
150 – 450% increase in patient
and hospital
visits
In 2001 (Asia only), 160
million workdays lost,
and for a pandemic,
6 billion workdays lost worldwide
Bioterrorism
Biodefense
Agroterrorism
Agents of Bioterrorism
Bacteria, Rickettisia,
Category
Toxins
A
B
C
Anthrax; Botulism;
Plague; Tularemia
Brucellosis; Epsilon
toxin of C.
perfringens;
Glanders;
Staphylococcus,
enterotoxin B; Q Fever
Multidrug-resistant
tuberculosis
Viruses
Smallpox
Viral Hemorrhagic
Fevers
Total
(%
Zoonotic)
6 (83%)
5 (80%)
Hantaviruses; Nipah 4 (80%)
virus; Tickborne
encephalitis viruses;
Yellow Fever
CDC’s Most Significant Global
Epidemics Over the Last Decade
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1993 – Hanta virus
1994 – Plague (India)
Ebola virus (Zaire)
1996 – New Variant of CJD
(UK)
H5N1 influenza (Hong
Kong)
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1998 – Nipah virus
(Malaysia)
1999 – West Nile
2000 – Rift Valley Fever
2001 – Anthrax
2002 – Norwalk-like
viruses
2003 - SARS
Implications of Emerging Diseases
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Political
Social
Economic
Psychological
Environmental
Animal-borne Epidemics
Out of Control: Threatening
the Nation’s Health – 2003
 A report from the Trust
for America’s Health
Findings from the Report
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U.S. lacks a national program to prevent and control
diseases that impact humans, animals and our food
There is no coordinated effort or single agency with a
“command and control” responsibility
There is a lack of effective communications with the public
about these diseases and their impact
Disease surveillance systems are not linked
Findings from the Report
(continued)
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Funding for bioterrorism has not adequately
supported efforts to counter zoonotic disease
threats, especially from the animal health
perspective and infrastructure
There is a fragmentation of jurisdictions,
authorities, statutes and research; e.g. 200
different government offices and programs
responding to 5 zoonotic diseases
Animal and public health are separated by culture
and organization
Microbial Threats to Health
Conclusions & Recommendations
1. Enhancing the global response capability
2. Improving global infectious disease surveillance
3. Rebuilding domestic public health capacity
4. Improving domestic surveillance through better
disease reporting (this includes both human
health and veterinary health)
5. Exploring innovative systems of surveillance
6. Developing and using diagnostics
Microbial Threats to Health
Conclusions & Recommendations
(continued)
7. Educating and training the microbial threat
workforce
8. Developing and producing vaccines
9. Developing and producing antimicrobial drugs
10. Controlling the use of antimicrobials
11. Controlling vectorborne and zoonotic diseases
12. Establishing a comprehensive infectious disease
research
13. Creating interdisciplinary infectious disease
centers
Preventing Emerging Infectious Diseases:
A Strategy for the 21st Century – CDC
Goal 1:
Goal 2:
Goal 3:
Goal 4:
Surveillance and Response
Applied Research
Prevention and Control
Infrastructure and Training
Public Health at the Crossroad
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New, inclusive vision of public health
Shift to focusing on causes of population health
Ensuring that population health is a central concern of
policymakers
Globalization of causes and issues
Socioeconomic disparities
Emerging threats due to interdependence
New team – expanded, integrated and transdisciplinary

Population health is a shift from an emphasis on
individual health to understanding the multiple
determinants of health.

Health is an outcome shaped by a wide range of
social, economic, natural, built, and political
environments that form a complex and everchanging dynamic. Because of this broad
perspective, public health teams themselves also
need to reflect this reality.