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Know The Facts First!

Facts about STDs

What Are STDs?

STD stands for sexually transmitted disease. STDs are passed through sexual activity with someone who is infected. Sexual activity can include vaginal, oral, and anal sex. There are a few STDs that can also be passed by skin-to-skin (genital-to-genital) contact.

You also may have heard the term STI, which stands for sexually transmitted infection. Although the terms are pretty much the same, some people use the term STI, instead of STD. The word "disease" can mean obvious signs or symptoms exist; however, often STDs have no signs or symptoms in people who are infected, or they have mild or temporary signs and symptoms that get overlooked or mistaken for something else.

  • About 1 in 4 teens has an STD.[1]
  • Anyone can get an STD from any kind of sex, not just vaginal.[2]
  • To best prevent pregnancy and STDs, it is important to use dual protection (using a condom in addition to a hormonal form of birth control).
  • If you are having sex, make STD testing part of your regular medical care. Find a local health care provider by visiting the CDC's National HIV & STD Testing Resources; learn what to do if you think you have an STD.

About 1 in 4 teens has an STD.

A study by the CDC examined nearly 1,000 adolescent girls in the United States (U.S.) looking for common STDs, including chlamydia, herpes (HSV), HPV, and trich. The study found that about 1 in 4 adolescent girls had at least one STD. Most girls in the study who were infected showed no symptoms and didn't even realize they were infected. The study estimates that about 3.2 million teen girls in the U.S. are likely infected with one of these STDs. The study noted the actual number of teens with STDs could be higher because some STDs — like syphilis, HIV, and gonorrhea — were not tested in this study.

Similar rates of STDs are likely among teen boys. A CDC study reveals that the annual number of new infections is roughly equal among young women and young men (49% of incident STDs occurs among young men, vs. 51% among young women [15–24 years old]).

Other important findings of the study include the following:

  • The most common STD was HPV.
  • Among those with an STD, 15% were infected with more than one STD.
  • 1 in 5 girls who had only one sex partner in their life had an STD.
  • Over 50% of teens reporting three or more sex partners in their life had an STD.

The study was based on 838 adolescents (ages 14-19) who were tested for the most common STDs: human papillomavirus (HPV) infection, chlamydia, herpes simplex virus type 2 (HSV-2) infection, and trichomoniasis as part of the 2003-2004 National Health and Nutrition Examination Survey.

What should I do if I think I have an STD?

Wondering if you might have an STD can be scary. It is important for you to get tested, and if you are infected, to get treated. There are places where you can get low-cost and confidential testing, where providers will offer supportive, nonjudgmental care. Health care providers are the best resource for getting the correct results and finding out for sure whether you have an STD.

Get Tested

Some STDs may have minor symptoms, which can be mistaken for other (less serious) infections. If you wait to get treatment for an STD or think that the infection has disappeared on its own, you put yourself at risk for serious complications later in life, such as being unable to get pregnant. And you could pass the STD on to a partner.

You may want to talk with a trusted family member or friend, too. If you feel like you can't talk to your parents, consider talking to another trusted adult, like a school nurse or a teacher who would be helpful. If there is no one you believe you can speak to in person, then you could call a hotline (1-800-CDC-INFO or 1-800-232-4636) or call ASHA's hotline (1-800-227-8922) and they can help answer questions you may have. To get tested, you will need to see a doctor or visit an STD testing center. You also have the option of testing specifically for HIV at home. If you buy your home test online, make sure the HIV test is FDA-approved. Learn what to do if you think you have an STD.

Will the health care provider tell my parents about my visit?

Most states require confidential STD testing. But if you are worried about your parents finding out, ask your doctor or clinic worker about their policies. If you'd like to know what the laws are in your state, the Guttmacher Institute offers detailed information here [pdf icon PDF 94K].

And while telling a parent can be frightening, remember that your parents will want to help you get the right treatment. They even could give you a ride to a doctor or clinic and help you pay for medication, if you need it. Click here for pointers on how to start the conversation with your parents.

  1. Forhan SE, et al. Prevalence of sexually transmitted infections among female adolescents aged 14 to 19 in the United States. Pediatrics. 2009 Dec; 124(6):1505-12.
  2. Prinstein M, et al. Adolescent Oral Sex, Peer Popularity, and Perceptions of Best Friends' Sexual Behavior. Journal of Pediatric Psychology, 2003 (28: 243-249).


What exactly is chlamydia?

Chlamydia is a common STD caused by bacteria. Chlamydia can damage a girl's reproductive organs, which can lead to infertility, meaning she is not able get pregnant later in life. It's called the quiet STD because most people who have chlamydia don't have symptoms or notice that something is wrong.

How do people get chlamydia?

A person can get chlamydia through vaginal sex, anal sex, or oral sex with an infected partner. Anyone who is sexually active can get chlamydia. A teenage girl, whose cervix (opening to the womb) is not fully matured, may have a greater chance of getting chlamydia.

Pregnant women who have chlamydia also can pass it on to their unborn child during childbirth if the infection is left untreated.

What are the symptoms of chlamydia?

Most people who become infected with chlamydia don't show any signs of having an STD. If there are symptoms, it may be one to three weeks after having sex. Signs to look for can include abnormal discharge, which is unusual fluid or mucus from the vagina, or a burning feeling when you urinate. Chlamydia also can cause pain or discomfort during sex, pain in the lower belly or back (sometimes with a fever), or bleeding after sex or between periods.

How can chlamydia be prevented?

The surest way to avoid STDs is not to have sex or to have sex with only one partner who has been tested, is not infected, and is having sex only with you. You can also lower your risk of getting chlamydia by using condoms all the time (from start to finish) and in the right way.

How is chlamydia diagnosed?

A swab is taken of the urethra (men), cervix (women), and/or rectum (for people who have had receptive anal sex). For women, the cervical swab is taken as part of a pelvic exam. Many providers also will use a urine test to diagnose chlamydia in men. Although a urine test can be performed in women, it is slightly less sensitive than a cervical swab and so is less often used. The Centers for Disease Control and Prevention (CDC) recommends yearly chlamydia testing of all sexually active women younger than 25 as well as all pregnant women.

How is chlamydia treated?

Chlamydia can be easily treated and cured with antibiotic pills.

How can I learn more about chlamydia? and CDC are great resources for easy-to-understand information about chlamydia.


What is genital herpes?

Genital herpes is a common STD caused by a virus. Two types of herpes viruses, herpes simplex virus type 1 (HSV1) and herpes simplex virus type 2 (HSV2), can cause an infection on or around the genitals. However, HSV1 more commonly infects the mouth or lips, while HSV2 more commonly infects the genitals. Nationwide, 16%, or about 1 in 6 people (14—49 years of age), have genital HSV2 infection.

How do people get genital herpes?

Sexual contact is the main way that the genital herpes virus spreads. It can be passed on from one person to another through vaginal sex, anal sex, and oral sex, but also skin-to-skin genital contact. Condoms, if used consistently and correctly, can help reduce the risk of genital herpes, but it is possible for areas of the skin that are not covered or protected by the condom to be infected with a herpes virus.

What are the symptoms of genital herpes?

Most people who have genital herpes do not know they are infected because there are often no symptoms. Some cases go unnoticed because symptoms are mild or get mistaken for insect bites or another skin condition. However if someone does have symptoms, they may appear as sores around the genitals, anus, or thighs. The first outbreak usually heals in two to four weeks, but sores may come back several times a year. A person having his/her first outbreak also may experience flu-like symptoms. It is possible that someone can pass genital herpes to a partner even when there aren't any symptoms.

It is important that women avoid contracting herpes during pregnancy because a newly acquired infection during late pregnancy poses a greater risk of transmission to the baby, which can lead to a fatal infection in babies. If a woman has active genital herpes at delivery, a cesarean delivery is usually performed. Fortunately, infection of a baby from a woman with herpes infection is rare.

How is genital herpes diagnosed?

Health care providers can diagnose genital herpes by looking at it or by taking a sample from the sore(s) and testing it in a lab. HSV infections can be diagnosed between outbreaks by the use of a blood test. Not all health clinics offer HSV testing, so be sure to ask for it if you are getting tested for STDs.

How is genital herpes treated?

There is no cure for genital herpes but there are treatments for its symptoms. Some medicines can prevent the blisters or make them go away faster. If you have several outbreaks in a year, a daily treatment may reduce your chance of passing the infection to your sex partners.

How can I learn more about genital herpes? and CDC are great resources for easy-to-understand information about genital herpes.


What is gonorrhea?

Gonorrhea is caused by a bacteria that can infect a woman's reproductive tract, including the cervix (opening to the womb), uterus (womb), and fallopian tubes (egg canals). It can infect the urethra (urine canal), mouth, throat, eyes, and anus in women and men.

How do people get gonorrhea?

Gonorrhea is spread through vaginal, anal, or oral sex.

Pregnant women who have gonorrhea also can pass it on to their unborn child during childbirth if the infection is left untreated.

How can gonorrhea be prevented?

The surest way to avoid STDs is not to have sex or to have sex only with one partner who has been tested, is not infected, and is having sex only with you. You also can lower your risk of getting gonorrhea by using condoms all the time (from start to finish) and in the right way.

What are the symptoms of gonorrhea?

Most people who are infected with gonorrhea have no symptoms. Anyone with gonorrhea is at risk of developing serious problems from the infection, whether or not they have symptoms. Gonorrhea is a common cause of pelvic inflammatory disease that can cause fevers or severe stomach pain. If left untreated, you may have problems getting pregnant.

The first symptoms can include a painful or burning sensation when urinating, increased vaginal discharge, or vaginal bleeding between periods. Symptoms of rectal infection in both men and women may include discharge, anal itching, soreness, bleeding, or painful bowel movements. Infections in the throat may cause a sore throat.

How is gonorrhea diagnosed?

Tests are available to diagnose gonorrhea. A doctor or nurse can obtain a sample for testing from the parts of the body likely to be infected (cervix, rectum, and mouth) and send the sample to a lab for testing. Gonorrhea sometimes can be diagnosed by getting a urine sample.

How is gonorrhea treated?

Gonorrhea can be treated and cured with antibiotics.

How can I learn more about gonorrhea? and CDC are great resources for easy-to-understand information about gonorrhea.


What is hepatitis B?

Hepatitis B is a liver disease caused by a virus that can be spread through sexual contact and causes inflammation of the liver. Inflammation means a painful, red swelling that happens when tissues of the body become injured or infected. Such swelling and pain can sometimes cause organs to not work properly. In the case of hepatitis B, it is the liver that is infected and may stop functioning as it should.

This infection can be prevented by a vaccine. Many young people were vaccinated at birth. Find out your vaccination status and get vaccinated if you haven't been.

How do people get hepatitis B?

Hepatitis B can be passed through contact with an infected person's blood, semen, or other body fluid. Remember that you can get hepatitis B in more ways than just sexual contact. Here are the many different ways in which you could get hepatitis B:

  • Having unprotected sex with an infected person
  • Sharing drug needles with an infected person
  • Being born to a mother with hepatitis B
  • Being tattooed or pierced with unsterilized tools that were used on an infected person
  • Getting an accidental stick with a needle that was used on an infected person
  • Using an infected person's razor or toothbrush

What are the symptoms of hepatitis B?

Hepatitis B usually has no symptoms. But when you do have symptoms, you might never associate them with hepatitis B because the symptoms are things you feel when you have a cold, the flu, or even food poisoning. Look below for a list of things that people infected with hepatitis B might experience:

  • Eyes and skin turn yellow (also known as "jaundice")
  • Bleeding continues for a much longer period of time for even simple cuts
  • Stomach and ankles swell
  • Easy to bruise
  • Feeling tired
  • Upset stomach
  • Fever
  • Loss of appetite
  • Diarrhea
  • Light-colored bowel movement
  • Dark yellow urine

But remember that most people with hepatitis B will not have any of these symptoms. Some people are able to fight the infection and clear the virus. For others, the infection remains and leads to a "chronic," or lifelong, illness.

How is hepatitis B treated?

There is no cure for hepatitis B, but there are medications available to help treat it. The best way to prevent hepatitis B is by getting the vaccine.

How can I learn more about hepatitis B? and CDC [pdf icon PDF 1M] are great resources for easy-to-understand information about hepatitis B.


What is HIV?

"HIV" stands for “human immunodeficiency virus.” If left untreated, HIV causes a viral infection that becomes AIDS, or Acquired Immune Deficiency Syndrome. The HIV virus attacks the body's immune system. Your immune system is what fights against infections to keep your body healthy. Today, many people with HIV are living longer and stronger lives. With proper lifelong care and treatment, many people can continue to take care of themselves and others.

How do people get HIV?

The HIV virus is found in, and can be passed through, five bodily fluids: semen, vaginal fluids, blood, anal mucus (fluids in your anus), and breast milk. These infected fluids are passed to another person in the following ways:

  • By sharing needles, including those used for tattoos and body piercings
  • By having unprotected sex (without a condom), including vaginal, oral, and anal sex
  • From a mother to her baby during birth or from breastfeeding; treatment is now available for moms with HIV to help prevent passing the virus to their babies

HIV is not spread through touching, hugging, or shaking hands with an infected person. It is not spread by coughing, sneezing, sharing glasses or dishes, or touching toilets or doorknobs. Pets and biting insects, like mosquitoes, do not spread the virus. Donating blood or getting a transfusion does not spread HIV either. This is because a new needle is used for each donor and all blood is tested before transfusion, so you never come in contact with infected blood.

What are the symptoms of HIV?

Some people experience the following symptoms within a few weeks of being exposed to HIV:

  • Fever
  • Headache
  • Swollen glands
  • Tiredness
  • Rash
  • Sore throat

Since these symptoms are common and may occur with other illnesses, a new infection may go unnoticed. If you have never been tested for HIV before, be sure to ask for one. CDC recommends that everyone, men and women, between the ages of 13 and 64 be tested for HIV at least once as part of routine health care.

How is HIV diagnosed?

The most common HIV tests use blood to detect HIV infection. Tests using saliva or urine also are available. Some tests take a few days for results, but rapid HIV tests can give results in about 20 minutes. All positive HIV tests must be followed up by another test to confirm the positive result. Results of this confirmatory test can take a few days to a few weeks.

Although home HIV testing kits are sometimes advertised through the internet, currently there are only two Food and Drug Administration (FDA) approved home HIV tests: the OraQuick In-home HIV Test and the Home Access HIV-1 Test System. If you buy your home test online, make sure the HIV test is FDA-approved.

How is HIV treated?

HIV cannot be cured but there are many treatments that people can take for the rest of their lives to help live much longer. Medications can slow the growth of the virus. Although these drugs don't kill the virus, they can keep the amount of virus in the blood low.

How can I learn more about HIV? and CDC are great resources for easy-to-understand information about HIV.


What is genital HPV infection?

Genital human papillomavirus (HPV) is the most common sexually transmitted virus. There are more than 40 HPV types that can infect the genital areas of males and females. These HPV types also can infect the mouth and throat.

How do people get HPV?

HPV is passed most often during vaginal and anal sex. HPV also may be passed during oral sex and skin-to-skin genital contact. HPV can be passed even when the infected partner has no symptoms. It also is possible to get more than one type of HPV.

Most infected persons do not know they are infected or that they are passing the virus on to a sex partner.

What are the symptoms of HPV?

In 90% of cases, the body's immune system clears HPV naturally within two years, so most people with HPV do not develop symptoms or health problems.

However, certain types of HPV can cause genital warts in males and females. Genital warts usually appear as a small bump or groups of bumps in the genital area. They can be small or large, raised or flat, or shaped like a cauliflower. Warts can appear within weeks or months after sexual contact with an infected partner – even if the infected partner has no signs of genital warts. Rarely, these types also can cause warts in the throat.

Other HPV types can cause cervical cancer (cancer of the cervix, or the opening of the womb) as well as cancers of the vulva (the area outside the opening to the vagina), vagina, penis, and anus, and some cancers of the head and neck (tongue, tonsils, and throat). Cervical cancer usually does not have symptoms until it is very advanced. For this reason, it is important for women to get regular screening tests for cervical cancer, which can find early signs of changes in the cervix so that problems that could turn into cancer can be treated.

How can HPV and its related problems be prevented?

Vaccines can protect against some of the most common types of HPV that can lead to disease and cancer. These vaccines are given in three shots and are recommended for boys ages 9 through 21 and girls ages 9 through 26. It is important to get all three doses to get the best protection.

If you choose to be sexually active, condoms may lower the risk of HPV and related diseases. To be most effective, condoms should be used with every sex act, from start to finish. But HPV can infect areas that are not covered by a condom, so condoms may not fully protect against HPV. To prevent cervical cancer, you should receive all three shots of the HPV vaccine. Girls also should receive Pap tests starting at age 21.

How is HPV treated?

There is no treatment for genital HPV itself. Most of the time, though, your body fights off the virus on its own. There are treatments for the health problems that genital HPV can cause, like genital warts, cervical changes, and cervical cancer. Even after genital warts are treated, the virus may remain in the body. This means that you may still pass HPV to your sex partners.

How can I learn more about HPV? and CDC are great resources for easy-to-understand information about HPV.


What is syphilis?

Syphilis is caused by bacteria. Syphilis is easy to cure in its early stages.

How do people get syphilis?

Syphilis can be spread through having vaginal, anal, or oral sex with someone who has the disease. Also, pregnant women with the disease can pass it on to their babies, and it can cause a miscarriage or death of a newborn.

What are the symptoms of syphilis?

Many people with syphilis infection may not notice symptoms for years but can have serious complications later on if the infection is not treated.

The initial (primary) stage of syphilis is a firm, round, small, and painless sore. The sore appears where the syphilis bacteria entered the body, on the external genitals, vagina, anus, or in the rectum. A sore also can be found on the lips and in the mouth. The sore lasts three to six weeks, and it can heal without treatment. These sores are often not recognized, so the infection can be passed from someone who doesn't realize he or she has the disease.

If adequate treatment is not administered, the infection moves on to the secondary stage. Rashes related to secondary syphilis (particularly on the palms of the hands or the soles of the feet) can appear as the sore is healing or several weeks after the sore has healed. The signs and symptoms of secondary syphilis will go away with or without treatment, but without treatment, the damage to your body may continue.

You can still acquire syphilis by having sex with a person in the primary or secondary stages of syphilis infection, even if they show no symptoms of having syphilis.

How can syphilis be prevented?

The surest way to avoid transmission of syphilis is to abstain from sexual intercourse, or to be in a long-term mutually monogamous relationship with a partner who has been tested and is known to be uninfected. Latex condoms, when used consistently and correctly, can reduce the risk of transmission of syphilis. To be most effective, they should be used with every sex act, from start to finish. Syphilis can infect areas that are not covered by a condom, so condoms may not fully protect against this disease.

How is syphilis treated?

One shot of penicillin, an antibiotic, will cure a person who has had syphilis for less than a year. More doses are needed to treat someone who has had syphilis over a year. For people who are allergic to penicillin, other antibiotics are available to treat syphilis.

How can I learn more about syphilis? and CDC are great resources for easy-to-understand information about syphilis.


What is trichomoniasis?

Trichomoniasis (also referred to as "trich") is a common STD caused by a microscopic parasite. Trich affects both women and men, although women will have more symptoms of this STD than men.

How do people get trich?

The vagina is the most common site of infection in women, and the urethra (urine canal) is the most common site of infection in men. Women can get trich by having sex with infected men or women, but men usually get this STD only from infected women. Trichomoniasis is spread through vaginal, oral, or anal sex and skin-to-skin genital contact.

What are the symptoms of trich?

Some women don't have symptoms from trichomoniasis, but those who do have symptoms get them between 5 and 28 days after becoming infected. Symptoms can include a foamy, yellow-green vaginal discharge with a strong odor. Some women also have discomfort during sex and when urinating as well as irritation and itching of the genital area. Sometimes women also have lower abdominal pain.

Most men with trich do not have signs or symptoms, but some men may temporarily have an irritation inside the penis, some minor discharge, or slight burning after urination or ejaculation.

In pregnant women, trich may cause premature birth (baby is born early) or low birth weight (baby's weight is less than 5.5 pounds).

How is trich diagnosed?

For both men and women, a health care provider must perform a physical examination and laboratory test to diagnose trichomoniasis. The parasite is harder to detect in men than in women. In women, a pelvic examination can reveal small red ulcerations (sores) on the vaginal wall or cervix.

How is trich treated?

Trichomoniasis can be treated and cured with antibiotics.

How can I learn more about trich? and CDC are great resources for easy-to-understand information about trich.

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