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Ebola—The Plague Fighters

Classroom Activity

Objective
To simulate and trace the spread of a virus.

• copy of "Pass It On" student handout (PDF or HTML)

• class set of envelopes
• 3 green strips of paper
• multiple white strips of paper

1. A major focus of the research work in Kikwit centered on tracing the spread of the virus. To simulate this process, conduct this activity.

2. Before beginning, prepare a class set of envelopes. Place a green paper strip in three envelopes and a white strip in the rest.

3. Distribute the envelopes. Explain that some people are carrying green, or infected, envelopes, and have students look inside. Tell students that they will circulate around the room for 60 seconds, until they hear Stop, and then they will whisper the color of their strip to the nearest person. Explain that students who hear green will now whisper green at all consecutive Stop times.

4. Do a trial run until students understand the procedure.

5. Now follow the procedure two times. Once the second round is done, tell all students who received a green slip or who heard green at the first stop to sit down but those who heard green at the second round to remain standing.

6. Repeat the procedure a third time. Tell students that if they heard green at the second Stop, to sit down. Twelve students will be sitting down at this point.

7. Next, distribute the "Pass It On" student handouts to students. Invite a volunteer to draw and fill in the Infection Tree on the chalkboard while the class works together to trace the origin of the virus.

Doctors identify victims, note when they became ill, and map their locations. Students must also track in order who became ill and when to trace the spread of their virus. Each student should try to remember who spoke to him or her. To find out who were the first people to be infected, students can work from the bottom or the middle of the Infection Tree. The six people standing who were infected in the final round will make up the bottom portion of the tree, while the six people who sat down after the second round will make up the top two layers of the tree. By tracing who spoke to whom, and when, students should be able to locate the first three index cases. Students in this simulation sit down after a certain round because they have effectively "died" from the disease and can no longer infect someone—a trait common to the Ebola virus. Other viruses may spread to more people because they don't kill their host as quickly. You can illustrate this difference by doing the activity again without having students sit down. In this version, the Infection Tree will increase exponentially after the first case of the virus is transmitted.