Summer Research Program for Science Teachers
Brooklyn International High School
Brooklyn, New York
August 2005
Course: Biology
Grade: 11th Grade
Unit: Molecular Genetics
Objective: Students will work in teams to apply biological concepts (immunology, virology, molecular genetics) to an infectious disease simulation based on the 2005 Angola Outbreak.
Overview of Lesson: This lesson uses problem based learning to guide students through the scientific process. Students are organized into teams of four. Ideally each team would have a computer available for internet research, but this is not essential for the lesson. Each team represents a CDC Special Pathogens task force. The lesson progresses in 4 separate parts. The teacher should pass out one part at a time to each team. If one team finishes before the others, they can work on defining the unfamiliar vocabulary words. After every team has completed the questions in Part I, the teacher should facilitate a class discussion of the results. Then pass out Part II and wait for the teams to complete the questions before reviewing the answers. This helps to build up the suspense as you add more layers of information to the situation. Students shouldn’t feel rushed or pressured to come up with the right answer. This activity is more about building critical thinking skills than having one exact answer to a question.
In the first part the students become familiar with their “jobs” as Special Pathogens Agents by researching on the CDC website. In Part II, the students are dispatched to respond to an outbreak in Angola. In Part III, the teams use their knowledge of blood and pathogens to formulate tentative diagnoses. In Part IV, the students apply their knowledge of immunology and molecular genetics (RT, PCR). Finally in Part V, the teams learn the true cause of the outbreak and explore internet sites to learn more about the current state of the outbreak. Students are evaluated based on their class participation, activity worksheets, and homework project.
Materials: Single sided copies of the worksheets (5)
Internet
Name: _________________________________________________ Date: _________________________________________________
Directions: Read the case study below. Discuss the questions with your team and record your answers on this worksheeet. You may use your class notes and the internet. List and define any new vocabulary words on a separate sheet of paper.
Introduction
You are a biologist working for the Centers for Disease Control (CDC) in Atlanta, Georgia.
You are working in the Special Pathogens Branch of the CDC where you and your colleagues study highly infectious viruses. Your daily work involves the investigation of viruses that cause several hemorrhagic (profuse bleeding) fevers, such as Ebola hemorrhagic fever, Lassa fever, and hantavirus pulmonary syndrome, and other recently identified and emerging viral diseases, such as Nipah virus encephalitis.
PART I
Go to www.cdc.gov/ncidod/dvrd/spb/mnpages/whoweare.htm.
1. List three job responsibilities of the Special Pathogens Agents:
2. Describe 2 diagnostic tools used by Special Pathogen Agents.
PART II
Your Special Pathogens team just received a call from a physician in Angola. She reported that at least one hundred people have become ill and are dying from a mysterious infection. Their symptoms include fever, vomiting, cough, diarrhea, and in some cases bleeding. The infection is highly contagious but she is unsure of exactly how it is transmitted.
With no time to lose, your team packs up the necessary supplies including the mobile lab which has facilities for routine hematologic and biochemical studies, as well as for basic bacter- iologic investigations. Serodiagnostic tests tests, enzyme-linked immunosorbent assays (ELISA), and RNA tests can be performed here as well. You carefully to pack your Biosafety Level 4 suits (as seen in the photos on the website) to protect you from exposure to airborne pathogens. Your team flies out the next morning for Angola.
1. What challenges will your team face in Angola?
2. Predict what local Angolan resources (personnel and equipment) you will have available to assist you.
3. Upon arrival, what immediate actions will your team take to manage the outbreak?
4. Describe the specific tests that you can do to learn more about the disease.
PART III
Five days have passed since you landed in Angola. The situation is devastating. Hundreds of people are sick and many have died. In the villages temporary hospitals have been made out of tents. But even the caregivers (families and friends) are frightened to get too close to the patients to give them food and water. You have seen many patients and they all have the same symptoms: fever, diarrhea, vomiting and bleeding. The disease seems to spread most rapidly in families living close together. You decide to send a blood sample from one of the victims for analysis at Americo Boa Vista Hospital in the capital city of Luanda.
1. What precautions will you take to ensure that the blood sample arrives safely in Luanda?
2. What molecules would you expect to find in a healthy blood sample? What about in an infected blood sample?
3. What information about the disease can the scientists get from the blood sample? Is it possible to diagnose a disease based on the blood sample? How?
4. Based on the information you have so far how would you diagnose the disease?
(Hint: The CDC website will be helpful here)
PART IV
The scientist working in the Luanda hospital isolates the viral RNA from the blood sample. Now she must perform a process called Polymerase Chain Reaction (PCR). PCR is the process by which a very small quantity of DNA is amplified (multiplied) into millions of copies.
1. How do you think the scientist was able to separate the viral RNA from the blood sample? Describe the steps would she have to take.
2. Why do you think it is helpful for the scientist to run the sample through the PCR machine?
3. What can the scientist learn from analyzing the PCR product - the millions of copies of viral cDNA? How will this help her to diagnose the disease?
4. Once the scientists have determined the type of virus, how can they use this information to help the hundreds of people who are sick and dying?
PART V
On May 20, 2005 the World Health Organization announced that 311 Angolans had died in this outbreak of viral hemorrhagic fever caused by the Marburg virus. Fortunately the number of new cases has declined since the peak in April.
Go to the World Health Organization website at:
www.who.int/features/2005/marburg/en/
Watch the slide show: “Bringing the Marburg outbreak under control”
1. What did the scientists, healthcare workers and other Angolans do to bring the outbreak under control?
2. What can be done in the future to prevent future outbreaks of Marburg virus?
HOMEWORK
Choose one of the following:
1. Write a paragraph describing the necessary training (education and experience) necessary to work as a CDC Special Pathogens Agent.
2. Write a newspaper article reporting on the Angola Outbreak.
3. Make a public health poster to inform Angolans about the outbreak and how to prevent the Marburg virus from spreading.
Standards:
National Science Standards:
Standard A: Students participate in an inquiry based activity using math and technology
Standard B: Content involves concepts in molecular genetics
Standard E: Students develop understanding of science and technology.
New York State Math, Science and Technology Standards:
Standard 1: Students will use scientific inquiry to pose questions, seek answers and
develop solutions.
Standard 2: Students will use technology to access and process information.
Standard 4: Students will understand and apply scientific concepts.