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
Paleolithic Age
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
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
Physical
Genetic and Environmental
Biological Factors
Factors Microbe
Human
Social, Political Ecological
and Economic Factors
Factors
Convergence Model (Microbial Threats to Health – IOM/NAS, 2003)
Factors in Emergence
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
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
60% of all human pathogens are zoonotic
80% of animal pathogens
Ecological generalists
New Dynamic
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
World 1 Advanced nations
(Advances in medicine and food)
World 2 Middle class
(Livestock Revolution)
World 3 People in destitution and poverty
(Sources of traditional pathogens)
El Nino
Leptospirosis
Hantavirus
Rift Valley fever
Vectors of Disease
Global Warming
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
Animals Humans
Waterborne
Disease
Microbial
Pathogens
Water Environment
Waterborne Zoonoses –
Global Threat
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
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
Campylobacter
Salmonella
E. coli 0157:H7
Yersinia
Listeria
Cryptosporidium
Cyclospora
Norwalk-like viruses
Livestock 2020 –
The Next Food Revolution
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
30% of US population are baby boomers
Immuno-compromised population
Movement and Interactions
of People and Commerce
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
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 Translocation
Human
Encroachment
encroachment
Introduction
Ex situ contact
“Spill over” & Wildlife EID
Ecological
“Spill back”
manipulation
Domestic Human EID
Animal EID Global travel
Agricultural Urbanization
Intensification Biomedical
manipulation
Technology and
Dasazak P. et.al. Industry
Science 2000 287:443
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
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
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, Total
Category Toxins Viruses (%
Zoonotic)
Anthrax; Botulism; Smallpox 6 (83%)
A Plague; Tularemia Viral Hemorrhagic
Fevers
Brucellosis; Epsilon 5 (80%)
B toxin of C.
perfringens;
Glanders;
Staphylococcus,
enterotoxin B; Q Fever
Multidrug-resistant Hantaviruses; Nipah 4 (80%)
C tuberculosis virus; Tickborne
encephalitis viruses;
Yellow Fever
CDC’s Most Significant Global
Epidemics Over the Last Decade
1993 – Hanta virus 1998 – Nipah virus
1994 – Plague (India) (Malaysia)
Ebola virus (Zaire) 1999 – West Nile
1996 – New Variant of CJD 2000 – Rift Valley Fever
(UK) 2001 – Anthrax
H5N1 influenza (Hong 2002 – Norwalk-like
Kong) viruses
2003 - SARS
Implications of Emerging Diseases
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
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)
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: Surveillance and Response
Goal 2: Applied Research
Goal 3: Prevention and Control
Goal 4: Infrastructure and Training
Public Health at the Crossroad
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 ever-
changing dynamic. Because of this broad
perspective, public health teams themselves also
need to reflect this reality.