Lesson Plan for Microbiology

Sally Jo Billingsley

Building a Pathway to Infection

OBJECTIVE: Students will understand how certain viruses may spread through a population by simulating the transmission of a communicable disease. Students will analyze data to identify the originally infected person and calculate the percent of infection after the activity.

MATERIALS: 1 film canister with lid for each student numbered 1-4 flour baking soda vinegar paper and pen or pencil

PREP: The majority of canisters must be filled with flour half way. Fill a small percentage of the canisters half way with baking soda. For a class of 18 fill (2), 26 (3). Flour should be placed in canisters numbered 2-4. Baking soda should be placed in the canisters numbered 1.

CLASSROOM PROCEDURE: Instruct students to write down two names of students in their classroom. Next, have each student to select a canister and return to their seat. Tell students that some of them have just contracted a virus. They have not been diagnosed, so they do not know if they have been infested. They are going to a party and will be sharing their drink with the two names on their list. If someone comes to them to share, they must share. They may not decline. Students are to go to each name on their list and exchange powder by pouring all the contents together mixing and pouring half back into each of their canisters. Students should write down the order of the students with whom they have exchanged powders. Once everyone has exchanged powders, have students return to their seats. One by one have students come up to a bowl or sink where the teacher will add vinegar into the canister. If baking soda is present, the powder will foam, if flour is present, no reaction will occur.

DISCUSSION: On the board, make a list of all the students who have been infected and the order they exchanged powders. Then make a list of all the students who have not been infected and the order they exchanged powders. Have the students work in groups to determine who they feel was the originator of the disease. Explain that there may be more than one carrier. When the student feel they have determined the original carrier have them to look at the bottom of their canister and identify the ones labeled (1).

EVALUATION: Have students write a reflective paragraph based on their current knowledge of virus transmission.

NOTE:

How Diseases Spread.

• Water

• Vectors

• Contaminated inanimate objects

• Direct contact

• Air