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Title: New Perspectives on Emerging Diseases, Biocomplexity and Teaching for Context


1
New Perspectives on Emerging Diseases,
Biocomplexity and Teaching for Context
  • From Microbial Threats to Health
  • Institute of Medicine, 2003

2
Emerging diseases/ Biocomplexity
http//www.nsf.gov/od/lpa/forum/bordogna/jb01sarno
ff/sld012.htm
3
Policy Forum Science, 4/23/04Scientific
Teaching
Science education should be founded
on scientific teaching. Scientific teaching
involves active learning strategies to engage
students in the process of science and
teaching methods that have been systematically
tested and shown to reach diverse students.
4
How?
  • Implementing change in lectures so that students
    are learning actively
  • Engaging students with important questions
  • Empowering students as investigators, both in
    their reading/ problem formulation and in the
    laboratory
  • RESOURCE LIST
  • with Science Policy Report
  • 4/23/04

5
Beloit College Mindset
Listhttp//www.beloit.edu/pubaff/releases/minds
et_2007.html
  • Most students entering college last fall were
    born in 1985
  • 1. John Kennedy and John Lennon have always been
    dead.
  • 2. Iraq has always been a problem.
  • 3. Genetic testing and DNA screening have always
    been available
  • 4. Paul Newman has always made salad dressing.
  • 5. The "evil empire" has moved from Moscow to
  • a setting in a distant galaxy far, far
    away.
  • 6. Bert and Ernie are old enough to be their
    parents.
  • 7. An automatic is a weapon, not a transmission.
  • 8. There has always been a screening test for
    AIDS.
  • 9. Computers have always fit in their backpacks

6
Microbiology Student Mindset List
They have never worried about polio and always
worried about AIDS. Anthrax is a weapon not a
soil microbe. Chlamydia has always been an STD
threat. Magic Johnson has been cured of
AIDS. Ebola has always been known. DNA is easily
copied and sequenced. Warnings for Toxic Shock
Syndrome are in all tampon boxes. Hasnt drug
design always been rational?
7
Recent news
Rare Infection Threatens to Spread in Blood
Supply By DONALD G. McNEIL Jr. New York
Times Published November 18, 2003 Dr. David A.
Leiby, a Chagas' disease expert, says the risk of
getting a transfusion of infected blood in the
United States is about 1 in 25,000. But in 1998
in Miami it was found to be 1 in 9,000, he said,
and in Los Angeles the same year, he measured it
at 1 in 5,400, up from 1 in 9,850 only two years
earlier. 530 Hepatitis Cases Linked to Pa.
Eatery By THE ASSOCIATED PRESS Published
November 19, 2003 PITTSBURGH (AP) -- The number
of cases of hepatitis A linked to a Mexican
restaurant rose to 530 Wednesday, but state
health officials said the outbreak has slowed
considerably since last week, when dozens of new
cases were being reported daily. Secretary of
Health Calvin Johnson said officials still
haven't determined whether tainted green onions
are behind the outbreak at the Chi-Chi's
restaurant, but were continuing to investigate.
8
Germ theory of disease
germ
disease
9
Epidemiological model of disease
agent
host
environment
10
Chagas Disease in the Blood Supply
  • Chagas is American trypanosomiasis- no treatment,
    chronic heart disease, colon blockage
  • Caused by protist, usually transmitted by
    arthropods
  • Adapted to new technologies- can survive in blood
    supply

11
WHOs warning
  • The risk of infection with Chagas disease is
    directly related to poverty the blood-sucking
    triatomine bug which transmits the parasite finds
    a favourable habitat in crevices in the walls and
    roofs of poor houses in rural areas and in the
    peripheral urban slums.

12
  • The rural/urban migration movements that occurred
    in Latin America in the 1970's and 1980's changed
    the traditional epidemiological pattern of Chagas
    disease and transformed it into an urban
    infection that can be transmitted by blood
    transfusion.

13
  • The figures of infection of blood in blood banks
    in some selected cities of the continent vary
    between 3.0 and 53.0 thus showing that the
    prevalence of T.cruzi-infected blood is higher
    than that of HIV infection and Hepatitis B and C.

How has the oranism changed? Is it genotypic or
phenotypic?
14
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15
Hepatitis A
  • Viral, acute disease
  • No carrier state
  • Spread by food, fecal contamination
  • Mortality rate 1
  • Vaccination available for health care workers,
    travelers
  • Green onions from Mexico implicated in ourbreak,
    not employees who didnt wash their hands
  • Will Chi-Chis survive this outbreak?

16
Reasons for disease emergence-Chi Chis outbreak
  • Eating out?
  • Young workers?
  • Imported produce?
  • Changing food preferences?
  • Immunocompromised eaters?
  • What is the process of tracking disease?
  • Viral subtyping
  • Epidemiological analysis

17
Factors in Disease Emergence 1992
  • Microbial adaptation and change
  • Economic development and land use
  • Human demographics and behavior
  • International travel and commerce
  • Technology and industry
  • Breakdown of public health measures

18
Factors in Disease Emergence 2003
  • Microbial adaptation and change
  • Human susceptibility to infection
  • Climate and weather
  • Changing ecosystems
  • Economic development and land use
  • Human demographics and behavior
  • International travel and commerce
  • Technology and industry
  • Breakdown of public health measures
  • Poverty and social inequality
  • War and famine
  • Lack of political will
  • Intent to do harm

from Microbial Threats to Health Institute of
Medicine, 2003
19
Factors in Disease Emergence 2003
  • Microbial adaptation and change AGENT
  • Human susceptibility to infection HOST
  • Climate and weather ENVIRONMENT
  • Changing ecosystems ENVIRONMENT
  • Economic development and land use ENVIRONMENT
  • Human demographics and behavior ENVIRONMENT
  • International travel and commerce ENVIRONMENT
  • Technology and industry ENVIRONMENT
  • Breakdown of public health measures ENVIRONMENT
  • Poverty and social inequality Structural
    Violence
  • War and famine Structural Violence
  • Lack of political will Structural Violence
  • Intent to do harm Structural Violence

20
Decresed immunity
Land use
technology
travel
environment
host
climate
Disease emergence
agent
Structural factors
Public health
Political will
war
Microbial evolution
21
susceptibility
Human behavior
technology
host
Microbial evolution
Land use
environment
agent
travel
Disease emergence
climate
Public health
Structural factors
War and famine
Political will
22
susceptibility
Human behavior
technology
host
Microbial evolution
Land use
environment
agent
travel
Disease emergence
climate
Public health
Structural factors
War and famine
Political will
23
While pathogenesis is related to factors of agent
and host, the emergence of new diseases is an
environmental and political phenomenon as well
24
Microbial adaptation and change
  • Microbes have enormous evolutionary potential,
    undergoing changes in pathogenicity and ability
    to avoid immune system-
  • Have ability to share traits for virulence
  • Evolutionary pressures to adapt are enhanced by
    human activities

25
The challenge of influenza
  • New strains develop frequently because of mixing
    of strains from pigs, chickens and wild birds
  • Factory farming practices increase risks
  • Fear that new strain could have impact of 1918
    influenza
  • Could this happen now?

http//www.civil.kyushu-u.ac.jp/suiken/ kawamura/s
eminar/earthstature/
26
What makes a Killer flu? How do mutations
affect vaccine effectiveness?
Functional Motions of Influenza Virus
Hemagglutinin (HA) A Structure-Based
Analytical Approach Isin B, Doruker P and
Bahar I. Biophys J.  2002 82(2)569-81
http//www.ccbb.pitt.edu/CCBBResearchFunMotInf.htm
27
Microbial adaptation and change
  • Microbial adaptations
  • Rapid reproduction- some bacteria have 20 minute
    generation cycles
  • Horizontal gene transfer
  • Frequent mutations, especially in RNA viruses
    like HIV, influenza
  • Microbes may become resistant to drugs but less
    fit- when drugs not used, will revert
  • What is the time/ space scale of microbial
    evolution?

28
Surveillance of H. pylori antibiotic resistance
in England and Wales, 2003
http//www.hpa.org.uk/infections/topics_az/helicob
acter/data.htm
29
Human susceptibility to infection
  • Impaired host immunity- HIV, transplants, aging
  • Malnutrition and effect on host resistance to
    infection
  • 150 million children under 5
  • Impaired phagocyte activity, cytokines, mucous
    membranes
  • Effects of specific nutrients, copper, vit A
  • Genetic polymorphisms
  • Sickle cell anemia and thalessemia
  • Glucose 6 phosphate dehydrogenase deficiency

30
http//www.worldbank.org/html/extdr/hnp/sector_str
ategy/hnpmaps.htm
31
Climate and weather
  • Vectors, animal reservoirs, microbes and humans
  • Hanta virus and El Nino weather in AZ
  • Cholera
  • Arthropod borne diseases like malaria, yellow
    fever and dengue
  • Mosquitoes in Beloit!!!

32
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33
Changing ecosystems
  • Forest growth reduces evaporation,
  • Crops increase local humidity
  • These change range of vectors
  • Dengue in Arizona- swamp coolers..
  • Reservoir abundance (mice and Hanta)
  • Moving mosquitoes
  • Culex like drier seasons (St Louis enchepal.)
  • Aedes aegypti, breed in containers Dengue

34
Why is dengue a greater problem in Mexico than
Texas?
http//www.usgcrp.gov/usgcrp/Library/nationalasses
sment/ overviewhealth.htm
Climate Change Impacts on the United States The
Potential Consequences of Climate Variability
and Change Overview  Human Health By the
National Assessment Synthesis Team, US Global
Change Research Program Published in 2000    
                         
                       
                       
                       
                       
                 
                         
                       
             
35
Economic development and land use
  • Suburban development, species diversity and Lyme
    disease
  • Dams and schistosomiasis- Nile and Yangtse

36
Snail fever outbreak hits China -
---------------------------------- China has
vowed stronger measures to contain the spread of
a potentially lethal parasitic worm, carried by
freshwater snails, that attacks the blood and
liver of humans, state media has reported. The
Government hopes research in its fight against
the disease, known as shistosomiasis, or snail
fever, will help identify infection sources and
develop new prevention methods, the China Daily
reported. It is believed that more than one
million Chinese are infected with the disease,
but, given the current prevalence of the carrier
snail, a total of 65 million Chinese are in
danger of being infected, previous reports said.
In 2003 alone, 843 000 Chinese were infected,
most of them living in frequently flooded areas
along the Yangtze River, where the carrier snail
has an ideal habitat, according to the paper. By
the 1980s, China thought that it had effectively
controlled snail fever, but a mixture of natural
disasters, and human error, has facilitated its
return. After a massive deluge along the Yangtze
6 years ago, the disease moved on to large,
previously unaffected areas. The disease has
been allowed to spread due to public ignorance
and the erosion of China's healthcare system,
the report said. ProMED, Vol 2004, 223, June
14, 2004
37
Human demographics and behavior
  • Child care
  • Population growth and limited infrastructure
    response
  • Aging of population- decreased immune response
  • Immunocompromised populations
  • Womens rights
  • Risky behaviors

38
HIV Prevalence in Teenagers in Kisumu, Kenya 1999
39
Technology and industry
  • Chi-chis and the food industry
  • Blood supply and safety
  • Organ transplantation, xenotransplantation
  • Animal husbandry- pig farms and chicken coops,
    aquaculture -
  • Antibiotics
  • Waste management

40
Transplant disaster
  • CDC reported in 11/2001 the story of a 23 year
    old man who received bone cartilage during
    reconstructive knee surgery and developed a fatal
    infection with Clostridium sordellii, an
    anaerobic spore and toxin forming organism
  • Several days later a man in Illinois received an
    infection from tissue from the same cadaver.
  • CDC investigators found 19 other tissues taken
    from the donor

41
International Travel and Commerce
  • Humans
  • Food
  • 95 of green onions in US imported from Mexico
  • Cruise ships (what a great environment)
  • Elderly passengers
  • Frequent new environments
  • Employees who can be carriers
  • Contaminated food and water
  • Some ships offer medical care
    and dialysis

42
Breakdown of public health measures
  • Tuberculosis in Russian jails- is the problem
    drug resistant TB or just poor treatment in poor
    environments?
  • Potential for spread of vaccine preventable
    diseases
  • Fear of loss of fertility with Polio vaccine in
    Muslim countries?

43
How do you treat HIV/AIDS from a clinic like
this?
In Kenya you begin to study the role of nutrition
because you can make an impact without
many resources
44
Poverty and social inequality
  • Is this biological? How?

45
War and famine
  • Most deaths in modern wars are not soldiers but
    civilians
  • Most deaths are not direct but indirect- result
    from destruction of water supply, malnutrition,
    loss of access to medical care
  • Increased migrations
  • Rape as a weapon of war
  • Famine- in war and as consequence of HIV

46
Intent to do harm
  • Role of individual vs nation state in political
    arena
  • Potential of genetically altered weapons
  • How much information should be available in the
    scientific literature? Should science be
    censored
  • Changing scenario of attack-
  • Terrorist scenario vs large attack
  • Characteristics of bioweapons- what do we need to
    know?

47
Political will
  • When the choice is 87 billion in Iraq or 3
    billion to stop AIDS
  • Countries that spend money on armies cut money to
    health services
  • Lost windows of opportunity-
  • Could countries have acted to stop AIDS?
  • Why was the response to SARS so rapid?

48
HIV stories
Mbekis stance How can a virus cause
a syndrome vs Achmats
activism Politics of drugs Who is Zackie
Achmat?
49
Political will and future scientists
  • Engaging students with science that matters will
    increase students who want to study science
  • Only if our students understand the context of
    what they are doing will they become ethical
    scientists
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