At the Party
Purpose: To explore epidemiological study while demonstrating how the spread of viruses is amplified through casual contact.
Background:
Viruses are nonliving infective agents that use a host’s cellular machinery for
the production of energy, replication, and distribution of new viral material. Viruses are spread through the air,
food, water, and through contact with an infective person.
Scenario: You are at a party of
friends and acquaintances. There is
a person among you who is infected with a virus that is very contagious.
The person looks just like everybody else and is not aware that they are
infected. As the party progresses you
will come in contact with five individuals.
One of them might possibly change your life!
Materials: Teachers:
Plastic cup full of fluid Fill a new numbered plastic cup 1/3
New pipette (dropper) full of distilled water for each
3M NaOH student in the class. In one of the cups
Phenylthalen put 10ml 3M NaOH.
Chart to document aquaintances
Prelab Questions:
1) What is a retrovirus?
2) Why are viruses considered non-living?
3) Name a retrovirus that is spread through casual contact.
a. Is there a vaccine for it?
b. How can its spread be prevented?
c. Do you think that it will ever be eradicated the way polio was eradicated?
Procedure:
1) Create a data table to be used in the recording of your contacts at the party.
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Name of Contact |
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1 |
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2 |
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3 |
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4 |
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5 |
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2) When the teacher says “MINGLE” you will find a person in the room and exchange fluid from your cup in the following fashion:.
a. While your cup is on a solid surface, withdraw 1 pipette full of solution from your cup and add it slowly to your acquaintances cup.
b. Be sure not to let the tip of your pipette touch your acquaintances solution or it may become contaminated.
c. Record the name of the person as your first contact
d. Wait for your teacher to say “MINGLE” again and repeat the procedure again with another person in the room.
3) Once you have come in contact with 5 individuals, return to your seat and place your cup at the top of your table with your chart below it.
4) The teacher will come by your table and add 2 drops phenylthalen to each cup.
a. If your water turns pink you have been infected!
5) Find patient zero (person who was originally infected).
a. If you were infected, look and see how many of the people you came in contact with are infected.
1. If all people you came in contact with are infected stay standing
2. If at least one person you came in contact with is not infected sit down. (you are not patient zero)
b. Look at the remaining people and see who you had contact with.
1. If you had contact with at least one of the people standing up stay standing.
2. If you did not have any contact with of the people standing sit down. (you are not patient zero)
c. Poll the class regarding the remaining people and see how many infected people came in contact (directly of indirectly) with each individual
1. The one with the most infected contacts is most possibly patient zero.
Post-lab Questions:
1) Who was most probably patient zero? Why do you believe this to be true? Why would a real scientist say “most probably”?
2) How does this demonstration mimic real life conditions of viral spread?
3) Epidemiology is the study of the spread of disease. If this were a real situation and you were the epidemiologist, how could you test subjects to find the origin of the outbreak? How easy or hard do you think it would be to carry out your plan?