How much do you really know about STIs?


By: Bambi Turner

6 Min Quiz

Image: Shutterstock

About This Quiz

Sexually-transmitted infections, or STIs, range from basic bacterial infections like chlamydia to incurable viruses like HIV. While many people avoid talking about these diseases because they are embarrassed or think it can't happen to them, sexual health is everyone's responsibility. Take our quiz to see how much you know about different STIs, how they spread, and how you can protect yourself.

Which of these activities DOES NOT spread HIV?

HIV is not spread through casual contact. That means you can share a drink or even a kiss with an infected person and not catch it. HIV is spread by sex, sharing needles and other more invasive methods of swapping blood.


Which of these conditions is linked to HPV?

HPV infection can result in genital warts, which is bad enough, but left untreated it can also result in cervical and other cancers. Fortunately, some types of HPV can be prevented with a readily-available vaccine.


What is the best way to know if you have an STI?

Many STIs have no symptoms at all, while others have symptoms that can be confused with other conditions. The best way to know your status is to get tested for STIs.


What is the treatment for chlamydia?

Chlamydia is one of the more common STIs and often causes burning, pain and abnormal discharge. Fortunately, it can be treated with a single round of antibiotics.


When is it OK to reuse a condom?

Reusing a condom leaves you exposed to STIs and pregnancy. Always dispose of condoms after each use and grab a new one every time you have sex.


Which of these can transmit an STI?

Don't think that a lack of penetration makes oral sex safe. All forms of sex, including oral, can transmit STIs, including HIV.


What is the only way to absolutely guarantee you won't get an STI?

The only way to be 100 percent sure you won't get an STI is to abstain from all forms of sex. Since this simply isn't practical for many adults, you can reduce your risk of picking up an infection by using condoms and avoiding risky behaviors.


Which of these actions is the best way to prevent an STI during sex?

Don't fall for the rumors: washing, douching or urinating after sex won't prevent you from picking up an STI if your partner is infected. The only way you can truly protect yourself is to abstain from sex or use condoms.


Which of these STIs can be cured with antibiotics?

While many STIs can be cured, others can only be managed because science has yet to find a cure. Both HIV and herpes are life-long illnesses, but chlamydia can be cured with a strong dose of antibiotics.


Which of these STIs can be prevented with a vaccine?

Both HPV and Hepatitis B can largely be prevented with vaccinations. Many babies get a Hep B vaccine, and the HPV vaccine is often given during the teen years.


Which of these STIs is known for breakouts of painful blisters and sores?

The herpes virus is transmitted through all forms of sex, and people suffering from this STI experience outbreaks of painful blisters and sores in the genital region.


Where's the best place to store your condoms?

Condoms should be stored in a cool, dry place. That means keep them in your dresser or nightstand and not in a place like your pocket or car, which can get too hot and damage the condoms -- limiting their effectiveness.


How do you catch pubic lice?

Pubic lice, aka crabs, can be caught via any sexual contact. That means you don't actually have to have intercourse to get them -- you can get them from simply lying naked near an infected person. An over-the-counter medicine eliminates almost every pubic lice infection if used correctly.


What percentage of teenagers pick up an STI each year?

One in four teens picks up an STI each year. By age 25, 50 percent of all adults will have had at least one STI. This means that using condoms and undergoing regular testing are particularly important for youth within that age group.


What percentage of Americans with HIV don't know they have it?

Around 15 percent, or one in seven Americans with HIV don't know they have it. Protect your partners and know your treatment options by getting tested if you suspect you could have HIV.


Which STI is most often referred to as "the clap"?

Gonorrhea has long been known as the clap. This may be linked to an old French term for brothel -- clapier -- where this STI ran rampant.


What percentage of doctors regularly screen for STIs?

When it comes to taking charge of your sexual health, knowledge is power. Keep in mind that only about a third of all doctors include STI testing as part of a standard health screen. That means with most doctors, if you want an STI test, you'll have to ask.


What percentage of people will pick up an STI in their lifetime?

Around half of the population will pick up an STI at some point in their lifetime. While many of these conditions are treatable, others are not. Incurable infections can only be managed to minimize impact.


Which age group gets the most new STIs each year?

Young people between the ages of 15 and 24 account for around 50 percent of all new STI diagnoses each year, even though people in this age group represent only around a quarter of the sexually active population in the U.S.


What percentage of the population has genital herpes?

Around 20 percent of the population, or one in five adults, have genital herpes. Even worse, 90 percent of them don't know it, making it easy to spread the disease to their partners.


What is the most common STI in the U.S.?

HPV, or human papillomavirus, is by far the most common STI in America. Nearly everyone who is sexually active will be infected at some point in their lives.


What is the first visible symptom of syphilis in most cases?

Most cases of syphilis reveal themselves with only a single sore. It's red, painless, round, and generally found on either the mouth or genitals. If you spot a sore like this, get treated, because later stages of syphilis pose some serious health risks.


Which of these STIs can't typically be prevented with a condom?

Herpes doesn't require sexual penetration to spread -- it spreads by simple contact with sores. That means a condom won't prevent transmission, especially if your partner has sores in an area not covered by the condom.


What causes trich, or Trichomoniasis?

Trich is an STI caused by transmission of a parasite. Most people who have this show no symptoms, though some women develop vaginitis. A dose of antibiotics eliminates the parasite and gets rid of trich.


What is the most common bacterial STI?

Chlamydia is the most common STI caused by a bacterial infection. While this means it's easy to treat with antibiotics, it shouldn't be taken lightly. Left untreated, this disease can lead to pelvic inflammatory disease, which can hinder fertility.


What is the average life expectancy for people in North America with HIV who take anti-viral medication?

People with HIV who start taking anti-viral medicine as soon as they are diagnosed live about as long as people who don't have the disease, with an average life expectancy in the 70s in much of North America -- though people of color, people who inject illegal drugs, and those who wait too long to start taking medicine tend to die sooner.


What is the most common gonorrhea symptom?

Most people with gonorrhea experience no symptoms, so the only way to know if you have it for sure is to get tested. While it can be treated with antibiotics, those who leave this condition unchecked risk harming their future fertility.


Which STI is associated with liver disease?

Hepatitis B can have longstanding effects on the liver if left untreated. Even more alarming, this STI is about 50 to 100 times more infectious than HIV. Protect yourself by getting a vaccine and practicing safe sex.


How does male circumcision affect HIV transmission risk?

Male circumcision reduces the risk of HIV infection in a heterosexual male by around 60 percent. The practice also reduces the risk of developing certain other STIs, including herpes and HPV.


Explore More Quizzes

About HowStuffWorks Play

How much do you know about dinosaurs? What is an octane rating? And how do you use a proper noun? Lucky for you, HowStuffWorks Play is here to help. Our award-winning website offers reliable, easy-to-understand explanations about how the world works. From fun quizzes that bring joy to your day, to compelling photography and fascinating lists, HowStuffWorks Play offers something for everyone. Sometimes we explain how stuff works, other times, we ask you, but we’re always exploring in the name of fun! Because learning is fun, so stick with us!