New Perspectives on Emerging Diseases, Biocomplexity and Teaching for Context

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New Perspectives on Emerging Diseases,
Biocomplexity and Teaching for Context

• From Microbial Threats to Health
• Institute of Medicine, 2003

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Emerging diseases/ Biocomplexity
http//www.nsf.gov/od/lpa/forum/bordogna/jb01sarno
ff/sld012.htm
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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.
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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

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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

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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?
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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.
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Germ theory of disease
germ
disease
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Epidemiological model of disease
agent
host
environment
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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

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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.

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• 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.

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• 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?
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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?

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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

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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

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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
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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

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Decresed immunity
Land use
technology
travel
environment
host
climate
Disease emergence
agent
Structural factors
Public health
Political will
war
Microbial evolution
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susceptibility
Human behavior
technology
host
Microbial evolution
Land use
environment
agent
travel
Disease emergence
climate
Public health
Structural factors
War and famine
Political will
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susceptibility
Human behavior
technology
host
Microbial evolution
Land use
environment
agent
travel
Disease emergence
climate
Public health
Structural factors
War and famine
Political will
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While pathogenesis is related to factors of agent
and host, the emergence of new diseases is an
environmental and political phenomenon as well
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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

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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/
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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
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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?

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Surveillance of H. pylori antibiotic resistance
in England and Wales, 2003
http//www.hpa.org.uk/infections/topics_az/helicob
acter/data.htm
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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

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http//www.worldbank.org/html/extdr/hnp/sector_str
ategy/hnpmaps.htm
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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!!!

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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

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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    
                         
                       
                       
                       
                       
                 
                         
                       
             
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Economic development and land use

• Suburban development, species diversity and Lyme
  disease
• Dams and schistosomiasis- Nile and Yangtse

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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
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Human demographics and behavior

• Child care
• Population growth and limited infrastructure
  response
• Aging of population- decreased immune response
• Immunocompromised populations
• Womens rights
• Risky behaviors

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HIV Prevalence in Teenagers in Kisumu, Kenya 1999
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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

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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

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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

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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?

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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
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Poverty and social inequality

• Is this biological? How?

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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

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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?

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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?

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HIV stories
Mbekis stance How can a virus cause
a syndrome vs Achmats
activism Politics of drugs Who is Zackie
Achmat?
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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