Download Infectious Disease Lab

Name: __________________________________________
Date: _________________________
Infectious Disease Lab
Background Information:
Infectious diseases occur when some type of pathogen enters your body and disrupts homeostasis by
damaging cells in certain tissues. These diseases can be passed on from organism to another. Occasionally this
occurs through animal bites, contaminated object, or from the environment. Most commonly these infectious
diseases are passed from person to person. This can occur from indirect contact, where you do not physically
touch the other person, or direct contact. Germs can be passed on in a sneeze or a hand shake.
When you have an infectious disease many times your bodily fluids carry the pathogens. Therefore, if
you r bodily fluids mix with someone else’s, the disease has been transmitted. For this lab we will be using
acquired immune deficiency syndrome (AIDS) as an example of an infectious disease.
AIDS was the number one cause of death for people between the ages of 25 – 44 in 1995. AIDS is
caused by the human immunodeficiency virus (HIV). This virus attacks a person’s immune system leaving
them vulnerable to infections and other diseases. The symptoms of AIDS are usually the symptoms caused by
having some other sort of disease, not from HIV itself. AIDS is an example of an infectious disease that is
passed on through the exchange of bodily fluids. HIV has been found in saliva, tears, nervous system tissue and
spinal fluid, blood, semen (including pre-seminal fluid, which is the liquid that comes out before ejaculation),
vaginal fluid, and breast milk. However, only blood, semen, vaginal secretions, and breast milk generally
transmit infection to others.
There is currently no cure for AIDS. There are
different treatment options, however. The most
successful option is antiretroviral therapy. This
therapy suppresses the virus’s ability to replicate. This
means there are less virus particles in the blood, doing
less damage to the immune system. The best way to
avoid this is to avoid behaviors that will put you at
risk for contracting AIDS. People at a higher risk of
contracting AIDS might be people who received
blood transfusions before 1985, babies born to
mothers who did not receive HIV therapy, sharing
needles, or having unprotected sex with unsafe
partners.
This is a diagram of what the human
immunodeficiency virus would look like
under an electron microscope.
Procedure:

Every student will receive a cup containing simulated bodily fluid. Each cup can be identified by the
letter on the bottom. This is your name for the purposes of this lab.

Only one of these cups of bodily fluids will be infected with HIV. (Don’t worry it’s not really HIV).

Every student will also receive a card with a number on it. This number is the number of people you will
exchange bodily fluids with.

When it is time you will exchange bodily fluids with the number of people on your card.
o To exchange bodily fluids you suck some of your bodily fluids into your pipette and squeeze it
into the other person’s cup.
o They then have to suck up some of their bodily fluids into the pipette and squeeze that back into
your cup.

Record the letters of each person you exchanged within the chart below. These letters must be written in
the same order that your exchanges occurred in.

When finished write your data on the board and copy the class results in your class data table.

The teacher will come around and squeeze some AIDS indicator solution into your cup.
o If the fluids turn pink or red, you have tested positive for HIV.
o If the fluids do not change color, you are negative for HIV.

Now, look back at the data your collected and try to figure out who started with AIDS and gave it to the
rest of the class.
Hypothesis:
__________________________________________________________________________________________
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You have Cup Letter: _________________
You will exchange with: _________ people
Data Table:
Order of
Exchange
Person Fluids were
Exchanged With
Total Number of Participants: _______________
Number of HIV Positive: ____________________
Percent of People who Contracted HIV: ___________
1
2
3
4
5
Risk Factor
Number of People with AIDS
Class Data Table:
Initial
Person
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
1st
Exchange
2nd
Exchange
3rd
Exchange
4th
Exchange
5th
Exchange
6th
Exchange
Post Lab Questions:
1. Who do you think patient zero was? Why do you think this? ___________________________________
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2. How do you think your number was related to your chances for contracting HIV? __________________
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3. Was your hypothesis close? Explain. ______________________________________________________
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4. What might make this lab different from how diseases are spread in reality? ______________________
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5. Why is it difficult to track a disease to its source (the first person to have it)? ______________________
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6. Explain what a virus is and why it is harmful. _______________________________________________
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7. Is AIDS an autoimmune disease? Explain. _________________________________________________
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8. AIDS is caused by a virus. What other organisms can cause infectious diseases? ___________________
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