General Statistics about STD/STIs in the United States
Ages / US PopulationAll ages / 308,827,000
.Under 5 years / 20,110,000
.5 to 9 years / 20,416,000
.10 to 14 years / 20,605,000
.15 to 19 years / 21,239,000
.20 to 24 years / 21,878,000
.25 to 29 years / 20,893,000
.30 to 34 years / 20,326,000
.35 to 39 years / 19,140,000
.40 to 44 years / 20,787,000
.45 to 49 years / 21,583,000
.50 to 54 years / 22,372,000
.55 to 59 years / 20,470,000
.60 to 64 years / 17,501,000
.65 to 69 years / 13,599,000
.70 to 74 years / 9,784,000
.75 to 79 years / 7,331,000
.80 to 84 years / 5,786,000
.85 years and over / 5,006,000
(Top picture) Roughly 20 million new STIs occur each year in the US, half of which are for young people (ages 15-24).
(Bottom picture) Roughly 110 million STIs currently exist in the US.
Sources:
Important note about male condoms: Condoms can be expected to provide different levels of protection for various STDs, depending on differences in how the diseases or infections are transmitted. Male condoms may not cover all infected areas or areas that could become infected.Thus, they are likely to provide greater protection against STDs that are transmitted only by genital fluids (STDs such as gonorrhea, chlamydia, trichomoniasis, and HIV infection) than against infections that are transmitted primarily by skin-to-skin contact, which may or may not infect areas covered by a condom (STDs such as genital herpes, human papillomavirus [HPV] infection, syphilis, and chancroid).
Clarification between STD vs. STI:
“STD and STI are two terms that often mean the same thing — but the ‘D’ stands for ‘disease,’ while the ‘I’ stands for ‘infection.’ Medically, infections are only called diseases when they cause symptoms, and many STIs don’t have any symptoms. So that’s why you may hear people say STIs – it’s technically more accurate, and also reminds people that there are often no symptoms so it’s important to get tested.”
“Sexually transmitted infection (STI) is another name for sexually transmitted disease (STD). The name STI is often preferred because there are a few STDs, such as chlamydia, that can infect a person without causing any actual disease (i.e. unpleasant symptoms). Someone without symptoms may not think of themselves as having a disease, but they may still have an infection that needs treating.”
Scenario #1: Engaging in sexual activity without any type of protection
Materials:
[clear] cups (8-12oz works well)
Water
Paper confetti —acts as a distractor
Sodium Hydroxide pellets—acts as the virus
Phenolphthalein—acts as a “revealer” by making water turn pink if the virus is present
Note: Sodium Hydroxide (NaOH) pellets and Phenolphthalein are cheap and readily available to chemistry lab instructors.
Preparation
Before the day of the activity: Prepare the virus (and “distractor”)
*In a separate quart-sized container, dissolve the Sodium Hydroxide (NaOH) pellets into a quart of water
*Fill a zip lock bag with paper confetti (or the holes from hole-punched paper)
On the day of the activity: Prepare the [clear] cups
*For this example, assume that a) the class has 30 students and b) 4 students have an STD
*Fill 26 cups below half full with plain water
*Fill 4 cups below half full with the Sodium Hydroxide solution
*If you want to use “distractors”, place a tablespoon of paper confetti in 4 cups (A. The confetti could go only in cups with plain water, or some confetti could go into both cups with clean water and cups with Sodium Hydroxide—you choose!)
General Sequence of the Activity
1) Ask students to come get their cup of liquid
2) Ask students to pick a partner and then…
a) Student A pours all of the contents of his/her cup into student B’s cup
b) Student B pours half of the contents back into Student A’s cup
c) This completes the first “cycle”
3) Repeat step 2 as many times as you (the teacher) desire
Recommendations:
*Have two cups with liquid set aside before the activity so that you can model for the students exactly how to pour the liquids during the activity.
*Write down any questions you want to ask before, during, and after the activity. A lot is going on during this activity and it is easy to reach information/logistical overload.
4) Once students have completed the required number of mixing cycles, put a drop of Phenolphthalein in each student’s cup. A student’s cup will turn PINK if it has the virus.
Note: You can tailor the setup according to 1) the number of students you have, 2) whether or not you want to use “distractors”
Questions you can ask:
1) Before the mixing…
How many of you think you have the virus right now?
How many of you think you will get the virus after, say, 3 cycles of interactions?
If I were to randomly select someone, what would be the probability he/she would have the virus?
2) After the mixing, but before students find out who has the virus…
Who were the original carriers of the virus? (Exploit perception bias)
How many of you think you have the virus now?
Did you use any strategies to minimize the chance that you would get the virus?
3) After students find out who had the virus…
Why do you think we used “distractors” in this activity?
Can you figure out who were the original carriers of the virus?
If I were to randomly select someone now, what would be the probability that he/she would have the virus?
How many cycles do you think we would need to have before everyone got the virus?
Scenario #2: Engaging in sexual activity with protection (male condom)
Background
In the preceding scenario, students carried out an activity that simulated the effects of engaging in sexual activities without any type of contractive protection. The students could see how quickly a virus could spread if no protection is used. The response to this phenomenon is to use contraceptives. However, contraceptives are not immune to failures. The following activity is designed to help students simulate contraceptive failures in the context of male condoms and take into account both STD transmissions as well as pregnancies upon contraceptive failures.
Materials
2 dice per student
Worksheet (see attached)
Preparation
Before the day of the activity: Prepare the virus
*On the back of [20%?] of the handouts that students will receive, lightly write in pencil in the top left corner the first letter of an STD. (For example, “H” could represent herpes.)
*Decide which days in the activity pregnancy can occur
*Prepare the handouts you plan to use for the activity (for example, the “contraceptive success/failure handout” and any handouts containing relevant studies or summaries of studies)
On the day of the activity:
*Establish with your class what the probability of contraceptive failure will be for the activity
*Once the probability of contraceptive failure is established, identify the roll that students will need to make in order for the contraceptive to “fail”. For example, if the class decides that the contraceptive will fail 5% of the time, then the class could decide that a roll of two six-sided dice resulting in “1,1” or “2,2” would be indicative of a contraceptive failure.
General Sequence of the Activity
1) Distribute to each student the “contraceptive success/failure handout”
2) Ask students to pick a partner and then…
a) Student A rolls both of his dice
i) If the dice do NOT produce a “1,1” or “2,2”, then the contraceptive did not fail. Thus, both students circle “NO” for the question “Did the contraceptive fail?” for that encounter and then proceed with the next cycle
ii) If the dice DO produce a “1,1” or “2,2”, then the contraceptive DID fail. Thus, both students circle “YES” for the question “Did the contraceptive fail?” for that encounter. Then, both students discreetly show each other the back of their handouts.
*If neither student has the STD, then the students proceed with the next cycle.
*If one student has the STD, then the other student write on his/her handout the letter of the STD he/she just contracted.
b) The students then decide to stay with their current partner or pick another partner. This cycle repeats until the worksheet is complete.
3) After the students have completed all 50 cycles, the teacher will announce to the students which encounters in which pregnancy was possible. (Pregnancies are possible roughly 2-3 out of every 28 days, so the teacher may choose 3-4 encounters for which pregnancies were possible—say, encounters #10, #20, #30, and #40.)
i) Students will look at their handout to see if their contraceptive failed on the dates that the teacher mentioned. If their contraceptive failed on the mentioned dates, then the student got pregnant or got someone else pregnant on those dates.
Questions you can ask:
*In this simulation, how many failures occurred? Pregnancies?New STDs?
*Based on this activity, discuss the validity of the claim “Using condoms will keep you safe.”
*Are there any ways to minimize/eliminate getting pregnant or getting an STD?
*See worksheet
The activity for Scenario #2 and corresponding worksheets were created by Luke Smith, Auburn University Montgomery.
Instructions for “With Protection” Scenario:
1. For each encounter, roll the dice. If you get a sum of 3, then your contraceptive failed.
2. If your contraceptive failed, discretely look on the BACK of your partner’s paper to see if he/she has a disease (denoted by a letter). If yes, then you now have that disease and must write the same letter on the back of your paper.
3. Each time you contract an STD, record on the back of your sheet the encounter on which it occurred.
Encounter # / Did the contraceptive fail? / Encounter # / Did the contraceptive fail?1 / YES NO / 26 / YES NO
2 / YES NO / 27 / YES NO
3 / YES NO / 28 / YES NO
4 / YES NO / 29 / YES NO
5 / YES NO / 30 / YES NO
6 / YES NO / 31 / YES NO
7 / YES NO / 32 / YES NO
8 / YES NO / 33 / YES NO
9 / YES NO / 34 / YES NO
10 / YES NO / 35 / YES NO
11 / YES NO / 36 / YES NO
12 / YES NO / 37 / YES NO
13 / YES NO / 38 / YES NO
14 / YES NO / 39 / YES NO
15 / YES NO / 40 / YES NO
16 / YES NO / 41 / YES NO
17 / YES NO / 42 / YES NO
18 / YES NO / 43 / YES NO
19 / YES NO / 44 / YES NO
20 / YES NO / 45 / YES NO
21 / YES NO / 46 / YES NO
22 / YES NO / 47 / YES NO
23 / YES NO / 48 / YES NO
24 / YES NO / 49 / YES NO
25 / YES NO / 50 / YES NO
Facts for this activity:
Condoms have a failure rate of approximately 5%.
At least 1 in 5 people have an STD.
A woman can get pregnant 2 days every month (28 day period)
Name: ______Related Worksheet
Part 1: Without Protection
There are 10 people in a room and two of them have a virus.
Before anyone does anything, what is the probability of selecting someone who has the virus? ______
Let’s assume that each of the 10 people have one encounter.
What is the probability now of selecting someone who has the virus? ______
Let’s assume that each of the 10 people have a second encounter.
What is the probability now of selecting someone who has the virus? ______
Let’s assume that each of the 10 people have yet another encounter (their 3rd encounter).
What is the probability of selecting someone who has the virus? ______
Part 2: With Protection
Assuming that condoms have a failure rate of 5%, 1 out of 5 people have an STD, and women can get pregnant 2 days out of every 28 day period…
What is the probability that on a given day, a girl is fertile? ______
What is the probability that on a given use, the condom fails? ______
What is the probability that in a single encounter, both the condom fails and the girl is fertile? ______
If we assume that the condom fails, what is the probability that a person will get an STD? ______
If we assume that the condom fails, what is the probability that a woman could get pregnant? ______
If we assume that a woman has an encounter while she is fertile, what is the probability that the condom will fail (and therefore the man could get her pregnant)? ______
If someone engaged in 50 encounters and used a condom, how many times on average would the condom fail? ______
What is the probability that someone could have 50 encounters and the condom work every time? ______
Name: ______Answer Key for Related Worksheet
Part 1: Without Protection
There are 10 people in a room and two of them have a virus.
Before anyone does anything, what is the probability of selecting someone who has the virus? _____2/10
Let’s assume that each of the 10 people have one encounter.
What is the probability now of selecting someone who has the virus? __between 2/10 and 4/10
Let’s assume that each of the 10 people have a second encounter.
What is the probability now of selecting someone who has the virus? ___between 2/10 and 8/10
Let’s assume that each of the 10 people have yet another encounter (their 3rd encounter).
What is the probability of selecting someone who has the virus? ____between 2/10 and 10/10
Part 2: With Protection
Assuming that condoms have a failure rate of 5%, 1 out of 5 people have an STD, and women can get pregnant 2 days out of every 28 day period…
What is the probability that on a given day, a girl is fertile? ______2/28
What is the probability that on a given use, the condom fails? ______5/100
What is the probability that in a single encounter, both the condom fails and the girl is fertile? ______5/100* 2/28
If we assume that the condom fails, what is the probability that a person will get an STD? ______1/5
If we assume that the condom fails, what is the probability that a woman could get pregnant? _____ 2/28
If we assume that a woman has an encounter while she is fertile, what is the probability that the condom will fail (and therefore the man could get her pregnant)? ______5/100
If someone engaged in 50 encounters and used a condom, how many times on average would the condom fail? ______50*.05
What is the probability that someone could have 50 encounters and the condom work every time? ______(.95)^50
This article came out within the last year. A statement on page 114 caught my attention.