AUTHOR: Marianne Barker, Carmel High School, One Carmel Pkwy., Mundelein, IL

TARGET GRADE LEVEL: 7-12

EDUCATIONAL OBJECTIVES: The students will investigate a re-emerging tropical disease, several careers that are involved  in fighting life-threatening diseases and managing natural resources, and several issues that complicate decisions about land and water use.

National Science Education Standards Addressed

SCIENCE TEACHING STANDARD: planning inquiry-based science programs

ASSESSMENT STANDARDS: focus on investigative reports, role-playing, developmentally appropriate tasks, and assessments set in familiar contexts

SCIENCE CONTENT STANDARDS:

• Unifying Concepts and Processes in Science (developing student abilities and understanding, developing explanations based on scientific information and evidence)
• Life Science Content Standard C, Grades 5-8 and 9-12 (Structure and Function in Living Systems, Reproduction and Heredity, Populations and Ecosystems, Diversity and Adaptations of Organisms, Molecular Basis of Heredity, Interdependence of Organisms, Behavior of Organisms)
• Science and Technology Content Standard E, Grades 5-8 and 9-12 (Abilities of Technological Design, Choosing between Alternative Solutions, Communicating Problems, Processing and Solving Problems)
• Life Science Standard F, Grades 9-12 (Personal and Community Health, Population Growth, Environmental Quality, Natural and Human-Induced Hazards, Science and Technology in Local, National, and Global Challenges)
• Science in Personal and Social Perspectives Content Standard F (Personal Health, Populations, Resources, and Environments, Natural Hazards, Risks and Benefits, Science and Technology in Society)
• History and Nature of Science Content Standard G (Science as a Human Endeavor, Nature of Science, History of Science, Historical Perspectives)

SCIENCE BACKGROUND:

In recent decades, there has been a synergism among global climate change, increasing virulence of pathogens, expanding ranges of disease vectors, and human effects such as urbanization, poverty and deforestation to produce large-scale epidemics of infectious disease. One of these diseases is dengue, itself believed to have evolved from yellow fever, which now has an especially virulent form, dengue hemorrhagic fever.

For further information, please refer to the section about dengue fever.

MATERIALS NEEDED:

• A role card for each student
• A copy of the topographical map of Saliente for each student
• A copy of the background information for each student

PROCEDURE:

Distribute duplicated materials to students at least one day in advance of activity, 2-3 days is preferable. The students should research their roles using printed, online, and personal resources. The activity is conducted as a "town meeting" in which each person should present his/her information and viewpoint regarding future development in Saliente. If possible, encourage students to dress for their roles. For large classes, some roles lend themselves to several representatives. For younger students or smaller classes, the teacher may choose to eliminate some roles. Cut the role descriptions apart and give the student only the relevant part.

BACKGROUND INFORMATION FOR SIMULATION: (to be given to each student)

Saliente is a country similar to Costa Rica in geography, climate, and location. Its longitude is approximately 83-86 degrees West and the latitude is approximately 8-11 degrees North. The approximate dimensions of Saliente are 400 km from North to South, and 200 km from West to East. The elevation of the country varies from sea level to nearly 4000 meters above sea level. Until the second half of the twentieth century, the population engaged in subsistence farming in the lowlands, and most of the country was covered in rain forest and cloud forest. During the past 30 years, much of the country has been deforested to grow coffee in the mountains, bananas in the lowlands, and grasslands to graze cattle. The low areas now need to be irrigated because of desertification, and the government believes it is necessary to construct a reservoir in the mountains because rainfall has become sporadic and runs off too quickly to grow crops. The Salina River will need to be dammed to form the reservoir, and to use for hydroelectric power. For decades, farmers in the low areas have suffered intermittent epidemics of dengue, a viral disease carried from human to human by the Aedes aegypti mosquito. The illness was usually nonfatal but was characterized by high fever, severe headache and muscle pain, diarrhea, and nosebleed. In the past decade a new more virulent strain of the virus has emerged that results in hemorrhaging and a 20% fatality rate. In addition, the coffee farmers in the mountains are falling ill from the virus, whereas in the past the climate at higher altitudes was too cool to support the survival of the mosquitoes.

In addition to the agriculture of Saliente, there is a large resort that attracted significant tourist trade until the outbreaks of dengue became more frequent and the climate became oppressively warm. A local entrepreneur is considering building a shoe factory to utilize the leather that is a by-product of the cattle ranching in the area. A meeting of the citizens of Saliente has been convened to decide what direction future development should take. Should a dam and reservoir be built at considerable expense and tax burden to the citizens? Should the mosquitoes be sprayed with pesticides to decrease the incidence of dengue fever?

ROLES TO BE ASSIGNED AND QUESTIONS TO GUIDE DEVELOPMENT OF VIEWPOINTS

FAMILY PHYSICIAN
This doctor has practiced medicine in Saliente for several years. (S)he is very worried about the increase in virulence of the dengue virus and the inability of conventional medications to combat the illness. The physician is friendly with the local native medicine practitioner and they often work as a team.

Questions to answer in preparing for this role:
What symptoms do your patients suffering from dengue display?
How are you treating the illness in your patients?
Do you treat dengue with antibiotics? Why or why not?

EPIDEMIOLOGIST FROM THE WORLD HEALTH ORGANIZATION
This physician studies infectious diseases, tries to isolate the pathogen(s) causing the diseases, and any vectors that spread the disease. The epidemiologist shares some of the same concerns as the sociologist. At the present time, the epidemiologist suspects an extra virulent strain of dengue virus, and an especially hardy strain of mosquito carrying it from victim to victim.

Questions to answer in preparing for this role:
What does an epidemiologist do? (Find more information than the role description suggests.)
Why are you in Saliente instead of in your "safe" lab?
Are you in favor of the construction of the dam and reservoir? (Why or why not?)
Do you want to isolate the dengue patients from other people? (Why or why not?)
Do you want to spray pesticides to kill mosquitoes? (Why or why not?)
Do you have an opinion as to why the dengue virus is more virulent now?

DEPARTMENT OF NATURAL RESOURCES (DNR) REPRESENTATIVE
Among your many responsibilities are mosquito control and the preservation of plants and animals in the country of  Saliente. In the past, there was heavy use of pesticides to control mosquito populations.

Questions to answer to prepare for this role:
What are the typical responsibilities of your position?
Why or why not are you currently spraying pesticides to kill mosquitoes?
What do you believe your position concerning mosquito control should be in the future?

Questions to answer to prepare for this role:
Explain how it is possible for a biome to be transformed from a rain forest
to a desert in just a few years.
What other reasons are there to preserve the rain forest and cloud forest?

NATIVE MEDICAL PRACTITIONER
This native expert in medicine had used an epiphyte found only in the cloud forest for medication to combat fever and severe muscular pain. The habitat of this epiphyte will be destroyed if the reservoir is built because the plant grows only at an elevation of 3000 to 3500 meters above sea level, and that area will be completely flooded by the reservoir.

Questions to answer to prepare for this role:
What is an epiphyte?
Why does this epiphyte need a cloud forest or a rain forest to survive?
Why can't the epiphyte be grown or cultivated on a farm?

BANANA FARMER
Needs a regular supply of fresh water to grow bananas, and this is not available since desertification occurred in Saliente.

Explain why you are in favor of or opposed to constructing the dam and reservoir.

COFFEE FARMER
Your coffee crops are being threatened by warmer temperatures, decreasing rainfall, and unavailability of coffee pickers because several of them are ill or have died from dengue fever. When you started your coffee plantation, the average temperature in the mountains was many degrees cooler, and you were never plagued by mosquitoes. Now the climate is oppressively warm, there are swarms of mosquitoes, and people fall ill regularly from dengue fever.

Questions to answer to develop this role:
Do you have any theory about why the changes which now threaten your plantation have occurred?
Develop your position in favor of or opposed to the construction of the dam and reservoir.

YOUNG CITIZENS OF SALIENTE
The young people of Saliente are unemployed or underemployed. They have been utilized as banana pickers or coffee pickers, and earn minimal wages. They would like to enjoy amenities such as television and refrigeration, and to be able to start and raise families of their own. At the present time, electricity is not available in all areas of Saliente, and jobs are so unrewarding that many young people are emigrating from their family land.

Explain why you are in favor of or opposed to the proposed development in Saliente.
Are you concerned about the potential damage or destruction of the rain forest biome? Why or why not?

REPRESENTATIVE OF THE DEPARTMENT OF TOURISM
The resort business has fallen off drastically because the climate is not so pleasant as it used to be, and the air conditioning at the resort is old and unreliable. It is frequently under repair, and guests are uncomfortable in the heat and humidity. In addition, there have been news stories about the fatalities from dengue fever in Saliente. You remember the years when mosquitoes were eradicated by spraying of insecticides, and the resorts were full of tourists.

Questions to answer to prepare for this role:
Explain why you are in favor of or opposed to spraying insecticides to kill mosquitoes.
Develop your position in the debate about whether or not to build the dam and reservoir.

HOTEL/RESORT OWNER AND MANAGER
The resort used to be a trendy vacation spot for the wealthy. Now the air conditioners are old, unreliable, frequently out of service for repairs, and use Freon (CFC's) as the refrigerant. The sticky weather, swarms of mosquitoes, and reports of dengue fever have seriously undermined the profitability of the resort business in Saliente.

Questions to answer to prepare for this role:
Why has your resort become unprofitable?
What amenities do your guests insist upon?
What do you need to do to renovate the resort?
Develop your position in the debate about whether or not to build the dam and reservoir.

Questions to answer to prepare for this role:
How many species of plants and animals are estimated to exist in the tropical rain forests?
How many species of plants and animals have not yet been identified and characterized in the rain forests?
How many species of plants in the rain forests are speculated to have medicinal properties?
Aside from the potential benefit to humans as medicines, is there any other reason to preserve the creatures of the rain forests?

SCIENTIST FROM PHARMACEUTICAL COMPANY IN NORTH AMERICA
There have been reports of the medicinal properties of an epiphyte found only in the cloud forests of Saliente. It grows naturally only at elevations of 3000 to 3500 meters above sea level, and has never been successfully cultivated elsewhere. Your company is very interested in acquiring the development rights to the drug that might be isolated from the epiphyte.

Questions to answer to prepare for this role:
How much money does it cost to develop the "average" new drug from discovery to marketing?
What steps must your company take to exploit the potential drug from the epiphyte?
Develop your position in favor of or opposed to the building of the dam and reservoir.
Do you have a "right" to express your viewpoint about environmental issues in Saliente?

REPRESENTATIVE OF ELECTRICAL POWER COMPANY OF SALIENTE
The power company supplies electricity for industry, the resort, and all the citizens of Saliente who have access to it. Currently, the power company is using some fossil fuels and some fermented plant products (ethyl alcohol) to supply fuel for the electrical plant.

Questions to answer to prepare for this role:
What benefits will you provide for each group of people represented at this meeting?
What are the products of the combustion of fossil fuels?
What are the products of the combustion of ethyl alcohol?
What would be the products of the operation of a hydroelectric plant?
Obviously, you have an agenda in Saliente; it is your job to convince the citizens that building the dam would be to their benefit. Do you really believe this? Why or why not?

INDUSTRIALIST
The industrialist wants to build a shoe factory in the lowlands of Saliente. This would be the first factory in the country.

Questions to answer to prepare for this role:
Why do you want to build a shoe factory in a rather undeveloped country like Saliente? Where would you get the leather for such an industry?
What is your position on using insecticides for mosquitoes and building a dam and reservoir in the mountains?

SOCIOLOGIST
The sociologist is concerned about the concentration of factory workers, construction workers (from construction of dam, reservoir, roads), and assorted support personnel in a congested urban setting that would result from rapid development in Saliente.

Questions to answer to prepare for this role:
Why are you concerned about urbanization (movement of people into city settings) in Saliente?
Why or why not could this concern be shared  with the epidemiologist?
If construction workers move into the area alone (unaccompanied by family) what social problems could this foster?
If construction workers move into the area accompanied by their families, what social problems could this engender? What services would need to be provided for the families?

Questions to answer to prepare for this role:
What is subsistence farming?
Is it sustainable?
What are your concerns about the building of a dam, reservoir, roads, and factories in Saliente? Are you in favor of or opposed to such development?
Are you in favor of or opposed to using insecticides to kill mosquitoes?
Are you in favor of or opposed to the drug company representative developing the epiphyte found in the mountains?

THE PRESIDENT OF SALIENTE
As the leader of the citizens of Saliente, you are interested in the growth of the economy, and the people taking their place in the developed world. Depending on the outcome of this meeting, you plan to approach the World Bank for funds to finance the development projects. At that time, you will need to convince the Bank that it will not lose money on those projects.

Questions to answer to prepare for this role:
Under the present circumstances, do you expect economic growth for Saliente?
How do you define "economic growth" for the average citizen of Saliente?
Does your country need to change for economic growth to occur? If so, in what way(s)?
Can you convince the citizens that any changes are desirable?

CIVIL ENGINEER
It is your responsibility to plan the safe and efficient building of the dam, reservoir, roads, bridges, etc., that are being discussed at this meeting. Most of the people here have never heard of a civil engineer.

Questions to answer to develop this role:
Explain your career to the citizens of Saliente?
What is your personal benefit in the projects being discussed at this meeting?
Develop your position in favor of or opposed to the construction of the dam and reservoir, etc., and the spraying of insecticides to control mosquitoes.
Will any citizens have to be relocated to accomplish your projects? If so, can you convince them that it will be to their benefit to move?

CONSTRUCTION COMPANY EXECUTIVE
You hope to win the contract to build the dam and roads, and possibly the factory that is proposed at this meeting.

Questions to answer to develop this role:
Where will you get the person-power to build the roads, dam, bridges, etc. that are proposed?
Can you offer any benefits to the people of Saliente if these projects are started and accomplished?
What will you give back to this country if you are awarded the assorted contracts that are involved?
Will you provide any services to the construction workers and their families so that the social fabric of Saliente is not too badly disturbed?

CLIMATOLOGIST
Your job is to explain to the citizens what you believe has caused the climate changes and resulting increase and spread of dengue fever to previously unaffected regions of Saliente.

Questions to answer to prepare this role: (Answer the questions emphasizing HUMAN influences on the assorted problems.)
Why has the climate become warmer in the country of Saliente, including the lowlands and the mountains?
Why do the farmers need to irrigate the bananas now, when there used to be adequate rainfall to grow them?
Why do the citizens need a reservoir now, when they did not a few decades ago?

(Optional: What is the temperature in degrees F at sea level and at 2000 meters above sea level in the preceding question?)

If the temperature increases 10 degrees C at sea level, at what altitude do the mosquitoes cease to be come viable in the mountains?
ASSESSMENT: Participation in meeting and preparation of roles

RESOURCE;
Garrett, Laurie. The Coming Plague: Newly Emerging Diseases in a World out of Balance; Penguin Books, New York, 1995.