HIV Transmission (Lindsey Boyd)

Title: HIV Transmission (HIV Cocktail Party)

Principles Investigated:

The ease in which HIV (communicable diseases) can be spread, optional: scientific method and inquiry, chemical reactions used for testing

Standards:

1.4.G- Identify why abstinence is the most effective method for the prevention of HIV, other STDs, and pregnancy

1.7.G- Describe the short- and long- term effects of HIV, AIDS, and other STDs.

3.2.G- Identify local resources concerning reproductive and sexual health, including all FDA-approved contraceptives, HIV/STD testing, and medical care.

5.4.G- Evaluate the risks and consequences associated with sexual activities including HIV, and other STDs, and pregnancy

8.2.G Advocate the respect for and the dignity of persons living with HIV or AIDS.

Materials:

Test tubes (enough for each student in the class)

Distilled water (from any grocery store)

Sodium Chloride

Silver nitrate solution (1 molar) concentration table and supplies can be found at:http://www.saltlakemetals.com/Silver_Nitrate_Solution.htm

Dropping bottle

Procedure:

Part 1- Exchange of fluids

“Set up a test tube rack containing the same number of test tubes as the number of students in the class. (Any container that is easy to pour from is good, but the clear test tubes or 15mL capped tubes are especially good because it is easy to see the silver nitrate reaction.) Fill one test tube with a solution of sodium chloride. (Somewhere around a 10% solution is good, but this is not an exact science. The teacher should test the solution to make sure it produces a positive reaction after 5-8 transfers.) This test tube represents the body fluids of an HIV infected person. Fill the other test tubes with distilled water (the chlorine in tap water reacts with the indicator, silver nitrate, giving a false positive). Prepare a dropping bottle of silver nitrate solution to serve as the HIV test. Care must be taken when using silver nitrate. Make a mental note of who picks up the “special” test tube when the game begins.” (The Cornell Institute for Biology Teachers “HIV Transmission.” Lord, Richard et al. 2008- See references)

Ask for four volunteers to abstain from the party. The other students will share “body fluids” by pouring some liquid from their test tube into the test tube of the person with whom they are sharing “body fluids”. The other person will pour some of his liquid back into the test tube of the first person. Have the students exchange fluids at least three times with three different people (the teacher may call out a cue for the students to exchange). After the exchanges, have each of the abstinent students choose a different person each to exchange their fluid with.

Part 2- HIV Testing

“Test each student by adding a drop of silver nitrate to each test tube. The teacher will assume the role of the doctor and administer an HIV test to each student at the end of the activity (the Doctor may want to wear a lab coat, rubber gloves, and a stethoscope). A white precipitate indicates a positive test; no precipitate is a negative test.

“**Other solutions may be used: phenolphthalein in the “HIV positive” test tube (test with sodium hydroxide, the positive result is a bright pink solution); a glucose solution in the “HIV positive” test tube (test with Benedict’s solution or testape).” (The Cornell Institute for Biology Teachers “HIV Transmission.” Lord, Richard et al. 2008- See references)

Student Prior Knowledge: Students should have a general understanding of what HIV is and how it is contracted. Students should also know and practice class ground rules particularly maturity and respect for all individuals in and outside of the classroom.

Explanation:

This can be a great activity for students, and has proved immensely successful in two of the past health classes I have taught. Without proper planning and facilitation, however, it can go terribly wrong. It is important to set up ground rules with the students far in advance, namely use of appropriate language and respect for all individuals. Consequences for such actions should be known. During the testing students tend to get rowdy, this is where rude and inappropriate remarks are often said, so be aware and prepared to discipline.

With any interactive activity, things can get chaotic so it is important to wait to pass out the test tubes until after the directions are given, and keep the students on task during the exchange of fluids. This can be done with a stopwatch or verbal cues. Student will want to stay in their particular area of the classroom so the instructor must ensure they move around.

Once the activity has been completed there should be ample time for discussion. I usually start the HIV/AIDS & STD unit with this activity then continue with information, statistics, ways to avoid risky situations, ways to say no, question and answer section, etc. Of course, if this activity is used to demonstrate other principles, that would be unnecessary.

Questions and Answers:

1. How is HIV contracted?

Having unprotected (without a condom) oral, vaginal, or anal sex with an infected partner; Sharing infected needles; being born to an infected mother (from mother to child during pregnancy, birth, or breast feeding); Other less common modes of transmission include blood transfusions, being bitten by an infected individual, contact between broken skin, wounds, etc. with an infected individual; getting “stuck” with a contaminated sharp object.

2. Who is at risk of catching the virus?

Anyone if they participate in high-risk behaviors including: having unprotected oral, vaginal, or anal sex; having multiple sexual partners; sharing needles; those who already have STDs; certain health care workers.

3. How can HIV be prevented?

Know your HIV status (get tested often if you are at risk); Abstain from sexual activity or be in monogamous relationship with an uninfected partner; limit number of sexual partners; Use condoms correctly and consistently; Get tested & treated for STDs & insist your partner also is; Do not share needles (for drug use, tattooing, piercing, or any other purpose); Get medical treatment immediately after possible exposure.

Applications to everyday life:

Deducing the source of a communicable disease (Biology)- Using scientific reasoning skills as epidemiologists do, the host of a disease can be identified and spread of communicable diseases can be limited.

Deducing the cause of a disease (scientific method)- Much like the Beri Beri case, by observing and analyzing conclusions of scientific research students can understand how scientists determine, using scientific method, what causes a disease.

Chemical testing (Chemistry)- using different chemicals to discover if a virus is or is not present. This is not limited to viruses, but also toxicology, pharmacology, agriculture, etc.

Photographs:

Liz and Nancy sharing bodily fluids

Positive test results (precipitate)

Videos:

HIV Test: The Top Ten Questions Answered- http://www.youtube.com/watch?v=hjDPCoj4ElA&feature=related

A Lifelong Battle: Teens living with HIV/AIDS- http://www.youtube.com/watch?v=x075Dh7tYLU

Get Tested for HIV (PSA)- http://www.youtube.com/watch?v=5us3PAEArPA

Resources:

The Cornell Institute for Biology Teachers “HIV Transmission.” Lord, Richard et al.- http://cibt.bio.cornell.edu/labs/dl/HIVT.PDF

AIDS and HIV Basic Information & Testing Information- http://cdc.gov/hiv/topics/basic/index.htm

HIV/STD local testing centers- http://www.hivla.org/search.cfm

HIV Statistics- http://cdc.gov/hiv/topics/surveillance/index.htm