AUA Summit - What are Sexually Transmitted Infections (STIs) or Diseases (STDs)?


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What are Sexually Transmitted Infections (STIs) or Diseases (STDs)?

Sexually transmitted infections (STIs) are also commonly called sexually transmitted diseases (STDs). They are the infections you get from another person through sexual contact. According to the CDC, there are more than 20 known types of STDs/STIs. In addition, over 20 million people in the United States are infected each year. About half of these people are age 15-24. Luckily, most STDs can be treated and cured.

How do you know if you have one? What is the best treatment? The information here should help answer these questions.

How do the male reproductive organs work?

The male reproductive system is specialized for the following functions:

  • To produce, maintain and transport sperm (the male reproductive cells) and protective fluid (semen)
  • To discharge sperm within the female reproductive tract
  • To produce and secrete male sex hormones

The male reproductive anatomy includes external structures which include the:

  • Penis
  • Scrotum
  • Testicles (testes)

The male reproductive anatomy includes internal structures which include the:

  • Vas Deferens
  • Ejaculatory ducts
  • Urethra
  • Seminal Vesicles
  • Prostate Gland
  • Bulbourethral Glands (Cowper’s Gland)

How do the female reproductive organs work?

The female reproductive system provides several functions. The ovaries produce the female egg cells, called the ova or oocytes. The oocytes are then transported to the fallopian tube where fertilization by a sperm may occur. The fertilized egg then moves to the uterus, where the uterine lining has thickened in response to the normal hormones of the reproductive cycle. Once in the uterus the fertilized egg can implant into thickened uterine lining and continue to develop. If fertilization does not take place, the uterine lining is shed as menstrual flow. In addition, the female reproductive system produces female sex hormones that maintain the reproductive cycle.

During menopause the female reproductive system gradually stops making the female hormones necessary for the reproductive cycle to work. At this point, menstrual cycles can become irregular and eventually stop. One year after menstrual cycles stop, the woman is considered to be menopausal.

The female reproductive anatomy includes both external and internal structures.

The function of the external female reproductive structures (the genital) is twofold: To enable sperm to enter the body and to protect the internal genital organs from infectious organisms.The main external structures of the female reproductive system include:

  • Labia Majora
  • Labia minora
  • Bartholin Glands
  • Clitoris

The female reproductive anatomy includes internal structures which include the:

  • Vagina
  • Uterus (Womb)
  • Ovaries
  • Fallopian Tubes


Often, there are no symptoms at all.

Men may experience the following symptoms:

  • Burning or itching in the penis
  • A drip (discharge) from the penis
  • Pain around pelvis
  • Sores, bumps or blisters on penis, anus, or mouth
  • Burning and pain with urine or with bowel movements
  • Having to go to the bathroom often

Women may experience the following symptoms:

  • Burning or itching in the vagina
  • A discharge or odor from the vagina
  • Pain around the pelvis
  • Bleeding from the vagina that is not normal
  • Pain deep inside during sex
  • Sores, bumps or blisters in the vagina, anus, or mouth
  • Burning and pain with urine or with bowel movements
  • Having to go to the bathroom often


What causes STDs?

Bacteria and viruses that grow in warm, moist places in the body cause STDs. They are passed from one person to another through sex. Infections can spread from the penis, vagina, mouth or anus. These infections can be minor or they can be very painful, even life threatening.

How do sexually transmitted infections spread?

They are spread through fluids in the body. Most often shared during vaginal, oral or anal sex. Some STDs pass from one person to another through infected blood. For example, among people who share infected drug needles. Or a mother may infect her child during pregnancy, childbirth or nursing.

STDs are not spread through casual contact. Shaking hands, sharing clothes, or sharing a toilet seat, for example, would not lead to STDs.

Who is at risk?

Anyone can get a STD. Teenagers and young adults have the highest risk. They are more likely to have many sex partners, and they may not know how to prevent problems. Street-drug users who use dirty needles are also at risk.


A health care professional can diagnose STIs. They will ask personal questions about your sex history. It’s important to be honest so you can get help. They may take a sample of fluid from the vagina or penis, or a blood test to confirm the problem. Laboratory tests can show what, if any, bacterial or viral STIs are present.

  • Blood tests can show if you have a disease that infects the blood.
  • Urine samples can show if you have a bacteria in your urine from an STI.
  • Fluid samples can show if you have active sores and help diagnose the type of infection.


What are the most common types of STIs/STDs and how are they treated?


This is the most common bacterial STI in the United States. An estimated 1.4 million new cases are diagnosed each year. It is transmitted through unprotected vaginal and anal sex.

Sometimes people have no sign that they have this disease. A man with chlamydia may feel pain when urinating or see fluid drip from the penis. A woman may bleed between periods, feel pain when urinating, see a discharge or feel mild pain in the lower belly. From anal sex, a patient may have anal bleeding or pain.

Once diagnosed, a person can be treated with an antibiotic. If untreated, it can cause serious damage to a woman's reproductive system. It can make it difficult or impossible to get pregnant.


Gonorrhea can cause infections in the genitals, rectum, and throat. Young people, age 15-24, are most often affected. You can get it by having unprotected vaginal, anal, or oral sex with someone who has the disease.

It may show no symptoms. Or, a person may find a discharge from the penis or vagina, and feel pain when urinating.

Gonorrhea is treated with antibiotics. If untreated, it can cause serious damage to a woman's reproductive system. It can make it difficult or impossible to get pregnant. In men, if this is left untreated it may cause urethral stricture.


This is a potentially life-threatening bacterial infection from vaginal, anal or oral sex. It can spread if the sores caused by syphilis touch the skin of a healthy person. Sores can be found on the penis, vagina, anus, in the rectum, or on the lips and mouth. Syphilis can also spread from an infected mother to her unborn baby.

Usually, the first symptom is a painless open sore. Sores can form on your genitals, or the palms of your hands and soles of your feet. The second stage rash can look like rough, red or reddish brown spots.

Penicillin is a successful treatment. If syphilis is not treated, it can remain in the body for years. It can cause serious problems including paralysis (unable to move body parts), mental disorders, damage to organs and even death.

Genital Herpes

This infection is very common. One in six people (age 14-49) has genital herpes. Many people don’t know they have it. This infection, caused by two viruses, Herpes Simplex Virus Type 1 (HSV-1) and Herpes Simplex Virus Type 2 (HSV-2).

The Herpes Simplex Virus Type 1 (HSV-1) is mostly spread by nonsexual contact but it can spread with oral sex. HSV-1 usually causes sores on the lips.

The Herpes Simplex Virus Type 2 (HSV-2) spreads when fluid from the infection touches a partner, often during sex. Genital blisters from HSV-2 may not be seen.

Blisters can form, break, cause pain and take weeks to heal. There is no known cure for HSV but symptoms can be treated with antiviral medicine.

Acquired Immune Deficiency Syndrome (AIDS)

AIDS results from an infection with the human immunodeficiency virus (HIV). It is not curable, and potentially deadly. It attacks the body's immune system.

Only blood, semen ( cum), pre-seminal fluid ( pre-cum), rectal fluids, vaginal fluids, and breast milk carry the virus. Infected needles or other sharp tools can spread AIDS as well. An infected mother can give her baby the virus during pregnancy, childbirth or nursing.

Some people have no signs if they get it. Others may feel like they have a bad flu for a long time. The virus can go un-noticed for many years. If you think you’ve been in contact with an infected person, you should get tested.

Antiviral, HIV medicines are available to improve the life and health of an infected person.

Hepatitis B (HBV)

This STI is a serious virus that attacks the liver. Effective vaccines since the 1990s have helped to prevent this infection. There are fewer cases every year. Blood, semen and body fluids shared during sex can spread the virus. Many people are born with the disease from their infected mother. Getting care to people with long-term HBV is important but often people have no clear symptoms.

When symptoms are present, they can include fever, headache, muscle aches, fatigue, poor appetite, vomiting and diarrhea. Since HBV attacks liver cells, it can lead to cirrhosis, liver cancer, liver failure and possibly death. Dark urine, abdominal pain and yellowing of the skin or eyes are signs of liver damage.

There is no known cure for hepatitis B. Still, medications to treat chronic infection will help. Vaccine is the best protection. Acute HBV has no treatment. Chronic HBV is treated with antiviral medicines, interferon treatment, or a liver transplant. Vaccine is the best prevention.

Genital Warts

These warts are caused by the human papillomavirus (HPV). HPV is the most common viral STI the United States. It is spread through vaginal or anal sex. It can be passed even when an infected person has no symptoms.

The warts that develop are painless, fleshy, cauliflower-looking bumps. They grow on the penis or in and around the entrance of the vagina or anus. HPV may eventually cause cervical cancer.

Fortunately, there is a successful vaccine to prevent HPV and genital warts. The vaccine is given to children age 11 or 12, or for people age 20-26. There is no known cure for genital warts. However, they can be treated with topical ointments. Sometimes they can be removed with minor surgical procedures (e.g., cautery (freezing or burning off the wart), chemicals, or laser). Vaccine is the best prevention.


This STI results from a parasite. It is spread through sexual contact from the penis or vagina. It mainly affects young, sexually active women. Uncircumcised men are found to spread the infection more. Only about 30% of people with this STI have symptoms.

Men with this STI may feel itching or irritation inside the penis. They may see discharge or feel burning after urination or ejaculation. Women may notice itching, burning, redness or soreness, discomfort with urination. Or, they may have an unusual discharge with a bad smell. Having trichomoniasis can make it feel unpleasant to have sex.

Without treatment, the infection can last for months or even years. Women with it may deliver underweight babies. Trichomoniasis can be easily treated with antibiotics.

After Treatment

Most STIs/STDs are cured after treatment. Some require life-long management with antiviral medicine. STDs can return with risky sexual behavior. Some people chose to get tested often, to ensure that they don’t have a STI. It is possible to prevent STIs and limit your chances of getting another.

Questions to Ask Your Doctor

How can STIs/STDs be prevented?

The only way to avoid a STI or STD is to have no sexual contact with an infected person. Other protections include:

  • Using a condom correctly, and always with sex
  • Having a sexual relationship with only one, long-term partner who has no infections
  • Limiting the number of sexual partners you have
  • Using clean needles if you are injecting drugs

Using latex condoms the right way helps to protect you and your partner. Still, condoms don’t cover everything. It is possible to get or spread infections even when using a condom.

Talk about STIs before you have sex with a new partner. This way you can make informed choices about risks you want to take with your sex life. The only way to truly prevent STIs/STDs is to avoid having sex.

If you or someone you know has symptoms like unusual discharge, burning during urination, or a sore in the genital area, please talk with a health care provider. You can get treatment and help.

Can STIs/STDs cause other health problems in women?

Some STIs can spread into a woman’s uterus and fallopian tubes. They can cause pelvic inflammatory disease. They can cause infertility and ectopic pregnancy (leading to fetal and possibly maternal death). STIs can be passed from mother to baby. Also, there are some links between STIs and cancer.

What if I am pregnant?

You can get treatment to prevent problems for your baby. If you are pregnant and have STD symptoms, please contact your doctor immediately. STDs during pregnancy should be addressed quickly.

Can I get a STI by open-mouth kissing?

Open-mouth kissing is considered a low-risk activity for the spread of STIs, especially HIV. Still, open-mouth kissing for a long time could damage the skin around the mouth and lips. This would allow HIV to pass from an infected person to a partner. Because of this risk, the CDC recommends using caution with an infected partner.

Should I be checked for STIs?

If you have had many sexual partners or have sex without protection, you should talk to a doctor. Whether or not you have symptoms, a doctor can help. Testing for STIs/STDs is very easy and routine. It’s better to take the test and get treated, than to risk health problems or infect others. HIV, HBV and syphilis testing are recommended. Cultures can be performed over time if you have unprotected sex with many partners.

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