Sexually Transmitted Infections (STIs)

Here you can learn more about different sexually transmitted infections (STIs). Read on to find out about symptoms, how they’re spread, and how you can get tested and treated.

Want to read about a particular STI? Click on the name to reveal its description.


Chlamydia is a Sexually Transmitted Infection (STI) caused by a bacteria. You can get it from vaginal (penis in vagina), anal (penis in butt), or oral (penis/vulva in mouth) sex (although chlamydia doesn’t seem to like the throat as much). Chlamydia is the most common STI in the US. Symptoms of Chlamydia in girls may be unusual discharge, burning/tingling when you pee, lower abdominal pain, pain during sex, or bleeding in between periods. Guys may have discharge from the penis, burning/tingling when you pee, pain or swelling in the testicles.

But only half of guys and only 1 in 4 girls with Chlamydia have symptoms. If left untreated, Chlamydia can mess with your reproductive system – possibly causing issues with fertility. This is why condoms (and other barriers such dental dams) and screening are so important! Chlamydia is easily treated with an antibiotic – although it is important to follow the instructions for taking it closely. To get tested for Chlamydia, all you have to do is pee in a cup!


Gonorrhea is a STI caused by a bacteria. Gonorrhea can also be passed through vaginal, anal, and oral sex. Girls may have burning/tingling when they pee, yellow-green discharge, and/or bleeding in between periods – or they may have no symptoms at all. Guys are more likely to have symptoms such as yellow-white discharge and/or burning/tingling when they pee.

If left untreated, it can cause infertility and in girls may lead to pelvic inflammatory disease. Again, this is why condoms and screening are important. Like Chlamydia, gonorrhea is curable with antibiotics. Most often you will get 2 different antibiotics – one that is given to you as a shot and some pills that you take. To get tested for gonorrhea, all you have to do is pee in a cup!

*If you have tested positive for either Chlamydia or gonorrhea, it is very important that any recent sex partners you have are notified and treated. You can do this yourself or the Minnesota Department of Health can notify them anonymously (meaning that your name will not be used or connected to them).


Herpes is a chronic virus that says in a person’s body for life. There are two types of herpes viruses: type 1 and type 2. Type 1 is more likely to cause infections of the mouth but may be passed to the genitals through oral-genital contact. Type 2 is more likely to cause genital infections but may cause infections of the mouth as well. Genital herpes is common- about one out of every six people aged 14 to 49 years have genital herpes in the U.S, and many people don’t know they have it.

You can get herpes by having oral, vaginal, or anal sex with someone who has the disease, even if they don’t have a visible sore. People with genital herpes get painful blisters on the vulva, penis, or around the anus. There are drugs that can be used to treat the first outbreak and reduce the number and severity of future outbreaks. Herpes is usually diagnosed by rubbing a cotton swab on an open sore and sending it in for testing.

Human Papilloma Virus (HPV)

HPV is a virus that affects the skin and membranes. Several types of HPV cause genital warts. Genital warts can be spread by oral, vagina, or anal sex as well as by skin to skin contact. It is very common, and you may not ever be aware that you have it. Warts might look like little bumps or they might be raised and look like cauliflower. A health care provider can remove visible warts by burning or freezing them off.


HIV is spread by direct contact with body fluids, such as blood, semen, vaginal fluid, and breast milk. When HIV has infected a person’s blood, the virus attacks the cells which normally protect people from infection and cancer. Usually an infected person has no symptoms at first, but they can get sicker of the years as the immune system gets weaker. Early diagnosis and treatment of HIV can keep an infected person healthier. You can NOT get or spread HIV through things like hugging, shaking hands, and sharing toilets.


Syphilis is a bacterial infection that can cause permanent damage if it’s not diagnosed and treated early. In the early stages, there may be a painless sore on the vulva or penis, and a skin rash as it progresses.  You can get syphilis by direct contact with a syphilis sore during anal, vaginal, or oral sex. Sores can be found on the penis, vagina, anus, in the rectum, or on the lips and in the mouth. Syphilis can also be spread from an infected mother to her unborn baby. Syphilis is treated with antibiotics and is easy to cure in its early stages.


Trichomoniasis, or “trich” is caused by a parasite. About 70% of infected people do not have any signs or symptoms.  When trichomoniasis does cause symptoms, they can range from mild irritation to severe inflammation. Some people with symptoms get them within a few days or weeks after being infected, but others do not develop symptoms until much later. Symptoms can come and go. Guys with trichomoniasis may feel itching or irritation inside the penis, burning after urination or ejaculation, or some discharge from the penis. Girls with trichomoniasis may notice itching, burning, and vaginal discharge. Trich is curable with antibiotics.

Molluscum Contagiosum

This is a big word for a virus! Molluscum is caused by the pox virus and it’ll look like small bumps with a dot in the center. They are usually painless but can sometimes get red, irritated, or swollen.   It can be spread by direct contact or by sharing a towel with someone who has it. Molluscum is treated with a medication that’s applied to the area, or by freezing and scraping the sores.


This isn’t a STI, but it can be spread by sexual contact. Scabies are mites that burrow under your skin. It’s spread by skin to skin or close body contact, or even by clothing, towels, and bedding.  The most common symptoms of scabies are intense itching and a pimple-like skin rash. It is treated with a medicated cream that’s applied neck to toe and left on for several hours. All bedding, towels, and clothing that have come into contact should also be washed, and everyone in the house should get treated.

Pelvic Inflammatory Disease (PID)

PID is often caused by untreated infections such as Chlamydia and gonorrhea, but other non-sexually transmitted bacteria can also cause it. PID is more likely to happen to women who:

  • Are under the age of 24
  • Have multiple sex partners
  • Have a partner with multiple sex partners
  • Have had PID in the past
  • Douche
  • Have bacterial vaginosis
  • Are in the first 5 days of their menstrual cycle

PID is treatable with antibiotics.

Bacterial Vaginosis

Bacterial Vaginosis (BV) is an infection caused by an overgrowth of unhealthy bacteria in the vagina. It is more common in sexually active women and is considered to be sexually associated, but it is not considered to be an STI. That means that a male partner of a woman with BV does not need to be treated. Having a new sex partner, multiple sex partners, and douching can upset the balance of bacteria in the vagina and put women at increased risk for getting BV. BV is not considered an STI, but having BV can increase your chances of getting an STI. BV may also affect women who have never had sex. You cannot get BV from toilet seats, bedding, or swimming pools. Symptoms include vaginal discharge and unpleasant odor. BV is treated with antibiotics.

Yeast Infection

A yeast infection occurs when there is overgrowth of the normal yeast in the vagina. This infection is relatively common — nearly 75% of all adult women have had at least one “yeast infection” in their lifetime. Women with a yeast infection experience genital itching, burning, and sometimes a “cottage cheese-like” vaginal discharge. It can be treated with oral or vaginal medication, and many over the counter creams are available for yeast infections.
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