At the conclusion of the lab, the student should be able to:
- Understand the properties of a virus
- Explain how viruses are spread through a population by sharing bodily fluids
A virus is not considered a living organism as it only contains DNA surrounded by a protein coat. However, viruses are serious infectious agents causes conditions such as AIDS, chicken pox, and herpes. Viruses must have a live host cell to reproduce. The virus takes over the protein building machinery of the cell to create new viruses to spread the infection. Viruses can infect many different types of organisms, both prokaryotic and eukaryotic.
One way a virus can be spread through a population is by sharing bodily fluids such as saliva, blood, or semen. We will demonstrate how quickly a virus can spread through today’s simulation activity.
Sharing Bodily Fluids
During this lab you will share “bodily fluids” with other students in the lab to simulate the spread of an infectious disease through a population.
- Obtain a numbered vial of solution and a plastic pipet from your instructor.
- Record your student name and vial number on the class data sheet.
- Share bodily fluids with another person in lab. Use the plastic pipet to withdraw solution from your vial and place 5 drops of your solution in another classmate’s vial. Your classmate will also share fluids with you in the same way. Return the cap to the vial and invert to mix.
- Record the name of the person you shared bodily fluids with in the table below.
- Exchange bodily fluids with another person following the directions above. Record the name of the person with whom you exchanged fluids.
- Exchange fluids with another student (different than the first two) and record his/her name below. You should complete three total fluid exchanges.
My vial #:_______________________
Record of Bodily Fluid Exchanges
Exchange 1: ______________________________
Exchange 2: ______________________________
Exchange 3: ______________________________
Your lab instructor will add a drop of the test reagent to determine if you are infected with the disease. If your sample turns pink then you are infected. If it turns yellow you are not infected. If you are positive for the disease you may have originally had the disease or you may have contracted the disease in lab today from sharing bodily fluids.
- Are you infected?
- Is it possible to determine if you were originally infected or did you contract the disease from someone during today’s lab?
As a class you will fill in Table 1 below. Include each person’s name. If your test result is positive put a plus sign (+) next to your name. If your result is negative put a negative sign (−) by your name. For those individuals that are positive, record whom they exchange fluids with and whether that person was positive or negative.
- How many people in the class are infected?
- Can you determine who was originally infected?
- If you can, whom do you think was originally infected?
- What do the class results show about the spread of disease through activities in which bodily fluids are shared?
Fill out a table similar to Table 1 for all members of your class. Be sure to add as many tables as there are students!
|Table 1. Class results for bodily fluid exchange activity|
|Student’s Name||Test result (+/−)||Exchange #1 (+/−)||Exchange #2 (+/−)||Exchange #3 (+/−)|
After you’ve completed Table 1, discuss with your lab group how this experiment simulates a real life infection through a population and answer the following questions.
- What are some ways that viruses are spread?
- What are some diseases that are spread by contact with bodily fluids?
- What are ways to prevent the spread of these diseases?