The term sexually transmitted disease (STD) is used to refer to a condition passed from one person to another through sexual contact. You can contract an STD by having unprotected vaginal, anal, or oral sex with someone who has the STD.

An STD may also be called a sexually transmitted infection (STI) or venereal disease (VD).

That doesn’t mean sex is the only way STDs are transmitted. Depending on the specific STD, infections may also be transmitted through sharing needles and breastfeeding.

It’s possible to contract an STD without developing symptoms. But some STDs cause obvious symptoms. In men, common symptoms include:

  • pain or discomfort during sex or urination
  • sores, bumps, or rashes on or around the penis, testicles, anus, buttocks, thighs, or mouth
  • unusual discharge or bleeding from the penis
  • painful or swollen testicles

Specific symptoms can vary, depending on the STD. Learn more about the symptoms of STDs in men.

In many cases, STDs don’t cause noticeable symptoms. When they do, common STD symptoms in women include:

  • pain or discomfort during sex or urination
  • sores, bumps, or rashes on or around the vagina, anus, buttocks, thighs, or mouth
  • unusual discharge or bleeding from the vagina
  • itchiness in or around the vagina

The specific symptoms can vary from one STD to another. Here’s more about the symptoms of STDs in women.

Many different types of infections can be transmitted sexually. The most common STDs are described below.

Chlamydia

A certain type of bacteria causes chlamydia. It’s the most commonly reported STD among Americans, notes the .

Many people with chlamydia have no noticeable symptoms. When symptoms do develop, they often include:

  • pain or discomfort during sex or urination
  • green or yellow discharge from the penis or vagina
  • pain in the lower abdomen

If left untreated, chlamydia can lead to:

If a pregnant woman has untreated chlamydia, she can pass it to her baby during birth. The baby may develop:

  • pneumonia
  • eye infections
  • blindness

Antibiotics can easily treat chlamydia. Read more about chlamydia, including how to prevent, recognize, and treat it.

HPV (human papillomavirus)

Human papillomavirus (HPV) is a virus that can be passed from one person to another through intimate skin-to-skin or sexual contact. There are many different strains of the virus. Some are more dangerous than others.

The most common symptom of HPV is warts on the genitals, mouth, or throat.

Some strains of HPV infection can lead to cancer, including:

  • oral cancer
  • cervical cancer
  • vulvar cancer
  • penile cancer
  • rectal cancer

While most cases of HPV don’t become cancerous, some strains of the virus are more likely to cause cancer than others. According to the , most cases of HPV-related cancer in the United States are caused by HPV 16 and HPV 18. These two strains of HPV account for 70 percent of all cervical cancer cases.

There’s no treatment for HPV. However, HPV infections often clear up on their own. There’s also a vaccine available to protect against some of the most dangerous strains, including HPV 16 and HPV 18.

If you contract HPV, proper testing and screenings can help your doctor assess and manage your risk of complications. Discover the steps you can take to protect yourself against HPV and its potential complications.

Syphilis

Syphilis is another bacterial infection. It often goes unnoticed in its early stages.

The first symptom to appear is a small round sore, known as a chancre. It can develop on your genitals, anus, or mouth. It’s painless but very infectious.

Later symptoms of syphilis can include:

  • rash
  • fatigue
  • fever
  • headaches
  • joint pain
  • weight loss
  • hair loss

If left untreated, late-stage syphilis can lead to:

  • loss of vision
  • loss of hearing
  • loss of memory
  • mental illness
  • infections of the brain or spinal cord
  • heart disease
  • death

Fortunately, if caught early enough, syphilis is easily treated with antibiotics. However, syphilis infection in a newborn can be fatal. That’s why it’s important for all pregnant women to be screened for syphilis.

The earlier syphilis is diagnosed and treated, the less damage it does. Find the information you need to recognize syphilis and stop it in its tracks.

HIV

HIV can damage the immune system and raise the risk of contracting other viruses or bacteria and certain cancers. If left untreated, it can lead to stage 3 HIV, known as AIDS. But with today’s treatment, many people living with HIV don’t ever develop AIDS.

In the early or acute stages, it’s easy to mistake the symptoms of HIV with those of the flu. For example, the early symptoms can include:

  • fever
  • chills
  • aches and pains
  • swollen lymph nodes
  • sore throat
  • headache
  • nausea
  • rashes

These initial symptoms typically clear within a month or so. From that point onward, a person can carry HIV without developing serious or persistent symptoms for . Other people may develop nonspecific symptoms, such as:

  • recurrent fatigue
  • fevers
  • headaches
  • stomach issues

There’s no cure for HIV yet, but treatment options are available to manage it. Early and effective treatment can help people with HIV live as long as those without HIV.

Proper treatment can also lower your chances of transmitting HIV to a sexual partner. In fact, treatment can potentially lower the amount of HIV in your body to undetectable levels. At undetectable levels, HIV can’t be transmitted to other people, reports the .

Without routine testing, many people with HIV don’t realize they have it. To promote early diagnosis and treatment, the recommends that everyone between the ages of 13 and 64 be tested at least once. People at high risk of HIV should be tested at least once a year, even if they don’t have symptoms.

Free and confidential testing can be found in all major cities and many public health clinics. A government tool for finding local testing services is available .

With recent advancements in testing and treatment, it’s possible to live a long and healthy life with HIV. Get the facts you need to protect yourself or your partner from HIV.

Gonorrhea

Gonorrhea is another common bacterial STD. It’s also known as “the clap.”

Many people with gonorrhea develop no symptoms. But when present, symptoms may include:

  • a white, yellow, beige, or green-colored discharge from the penis or vagina
  • pain or discomfort during sex or urination
  • more frequent urination than usual
  • itching around the genitals
  • sore throat

If left untreated, gonorrhea can lead to:

It’s possible for a mother to pass gonorrhea onto a newborn during childbirth. When that happens, gonorrhea can cause serious health problems in the baby. That’s why many doctors encourage pregnant women to get tested and treated for potential STDs.

Gonorrhea can usually be treated with antibiotics. Learn more about the symptoms, treatment options, and long-term outlook for people with gonorrhea.

Pubic lice (‘crabs’)

“Crabs” is another name for pubic lice. They’re tiny insects that can take up residence on your pubic hair. Like head lice and body lice, they feed on human blood.

Common symptoms of pubic lice include:

  • itching around the genitals or anus
  • small pink or red bumps around the genitals or anus
  • low-grade fever
  • lack of energy
  • irritability

You might also be able to see the lice or their tiny white eggs around the roots of pubic hair. A magnifying glass can help you spot them.

If left untreated, pubic lice can spread to other people through skin-to-skin contact or shared clothing, bedding, or towels. Scratched bites can also become infected. It’s best to treat pubic lice infestations immediately.

If you have pubic lice, you can use over-the-counter topical treatments and tweezers to remove them from your body. It’s also important to clean your clothes, bedding, towels, and home. Here’s more on how to get rid of pubic lice and prevent reinfection.

Trichomoniasis

Trichomoniasis is also known as “trich.” It’s caused by a tiny protozoan organism that can be passed from one person to another through genital contact.

According to the , less than one-third of people with trich develop symptoms. When symptoms do develop, they may include:

  • discharge from the vagina or penis
  • burning or itching around the vagina or penis
  • pain or discomfort during urination or sex
  • frequent urination

In women, trich-related discharge often has an unpleasant or “fishy” smell.

If left untreated, trich can lead to:

Trich can be treated with antibiotics. Learn how to recognize trich early to get treatment sooner.

Herpes

Herpes is the shortened name for the herpes simplex virus (HSV). There are two main strains of the virus, HSV-1 and HSV-2. Both can be transmitted sexually. It’s a very common STD. The CDC estimates more than people ages 14 to 49 have herpes in the United States.

HSV-1 primarily causes oral herpes, which is responsible for cold sores. However, HSV-1 can also be passed from one person’s mouth to another person’s genitals during oral sex. When this happens, HSV-1 can cause genital herpes.

HSV-2 primarily causes genital herpes.

The most common symptom of herpes is blistery sores. In the case of genital herpes, these sores develop on or around the genitals. In oral herpes, they develop on or around the mouth.

Herpes sores generally crust over and heal within a few weeks. The first outbreak is usually the most painful. Outbreaks typically become less painful and frequent over time.

If a pregnant woman has herpes, she can potentially pass it to her fetus in the womb or to her newborn infant during childbirth. This so-called congenital herpes can be very dangerous to newborns. That’s why it’s beneficial for pregnant women to become aware of their HSV status.

There’s no cure for herpes yet. But medications are available to help control outbreaks and alleviate the pain of herpes sores. The same medications can also lower your chances of passing herpes to your sexual partner.

Effective treatment and safe sexual practices can help you lead a comfortable life with herpes and protect others from the virus. Get the information you need to prevent, recognize, and manage herpes.

Other STDs

Other, less common STDs include:

Vaginal and anal sex aren’t the only way STDs are transmitted. It’s also possible to contract or transmit an STD through oral sex. In other words, STDs can be passed from one person’s genitals to another person’s mouth or throat and vice versa.

Oral STDs aren’t always noticeable. When they do cause symptoms, they often include a sore throat or sores around the mouth or throat. Learn more about the potential symptoms and treatment options for oral STDs.

Many STDs are curable. For example, the following STDs can be cured with antibiotics or other treatments:

  • chlamydia
  • syphilis
  • gonorrhea
  • crabs
  • trichomoniasis

Others can’t be cured. For example, the following STDs are currently incurable:

  • HPV
  • HIV
  • herpes

Even if an STD can’t be cured, however, it can still be managed. It’s still important to get an early diagnosis. Treatment options are often available to help alleviate symptoms and lower your chances of transmitting the STD to someone else. Take a moment to learn more about curable and incurable STDs.

It’s possible for pregnant women to transmit STDs to the fetus during pregnancy or newborn during childbirth. In newborns, STDs can cause complications. In some cases, they can be life-threatening.

To help prevent STDs in newborns, doctors often encourage pregnant women to be tested and treated for potential STDs. Your doctor might recommend STD testing even if you don’t have symptoms.

If you test positive for one or more STDs while pregnant, your doctor might prescribe antibiotics, antiviral medications, or other treatments. In some cases, they might encourage you to give birth via a cesarean delivery to lower the risk of transmission during childbirth.

In most cases, doctors can’t diagnose STDs based on symptoms alone. If your doctor or other healthcare provider suspects you might have an STD, they’ll likely recommend tests to check.

Depending on your sexual history, your healthcare provider might recommend STD testing even if you don’t have symptoms. This is because STDs don’t cause noticeable symptoms in many cases. But even symptom-free STDs can cause damage or be passed to other people.

Healthcare providers can diagnose most STDs using a urine or blood test. They may also take a swab of your genitals. If you’ve developed any sores, they may take swabs of those, too.

You can get tested for STDs at your doctor’s office or a sexual health clinic.

Home testing kits are also available for some STDs, but they may not always be reliable. Use them with caution. Check to see if the U.S. Food and Drug Administration has approved the testing kit before buying it.

It’s important to know that a Pap smear isn’t an STD test. A Pap smear checks for the presence of precancerous cells on the cervix. While it may also be combined with an HPV test, a negative Pap smear doesn’t mean you don’t have any STDs.

If you’ve had any type of sex, it’s a good idea to ask your healthcare provider about STD testing. Some people may benefit from more frequent testing than others. Find out if you should be tested for STDs and what the tests involve.

The recommended treatment for STDs varies, depending on what STD you have. It’s very important that you and your sexual partner be successfully treated for STDs before resuming sexual activity. Otherwise, you can pass an infection back and forth between you.

Bacterial STDs

Usually, antibiotics can easily treat bacterial infections.

It’s important to take all your antibiotics as prescribed. Continue taking them even if you feel better before you finish taking all of them. Let your doctor know if your symptoms don’t go away or return after you’ve taken all of your prescribed medication.

Viral STDs

Antibiotics can’t treat viral STDs. While most viral infections have no cure, some can clear on their own. And in many cases, treatment options are available to relieve symptoms and reduce the risk of transmission.

For example, medications are available to reduce the frequency and severity of herpes outbreaks. Likewise, treatment can help stop the progression of HIV. Furthermore, antiviral drugs can lower your risk of transmitting HIV to someone else.

Other STDs

Some STDs are caused by neither viruses nor bacteria. Instead, they’re caused by other small organisms. Examples include:

  • pubic lice
  • trichomoniasis
  • scabies

These STDs are usually treatable with oral or topical medications. Ask your doctor or other healthcare provider for more information about your condition and treatment options.

Avoiding sexual contact is the only foolproof way to avoid STDs. But if you do have vaginal, anal, or oral sex, there are ways to make it safer.

When used properly, condoms provide effective protection against many STDs. For optimal protection, it’s important to use condoms during vaginal, anal, and oral sex. Dental dams can also provide protection during oral sex.

Condoms are generally effective at preventing STDs that spread through fluids, such as semen or blood. But they can’t fully protect against STDs that spread from skin to skin. If your condom doesn’t cover the infected area of skin, you can still contract an STD or pass it to your partner.

Condoms can help protect against not only STDs, but also unwanted pregnancy.

In contrast, many other types of birth control lower the risk of unwanted pregnancy but not STDs. For example, the following forms of birth control don’t protect against STDs:

Regular STD screening is a good idea for anyone who’s sexually active. It’s particularly important for those with a new partner or multiple partners. Early diagnosis and treatment can help stop the spread of infections.

Before having sex with a new partner, it’s important to discuss your sexual history. Both of you should also be screened for STDs by a healthcare professional. Since STDs often have no symptoms, testing is the only way to know for sure if you have one.

When discussing STD test results, it’s important to ask your partner what they’ve been tested for. Many people assume their doctors have screened them for STDs as part of their regular care, but that’s not always true. You need to ask your doctor for specific STD tests to ensure you take them.

If your partner tests positive for an STD, it’s important for them to follow their healthcare provider’s recommended treatment plan. You can also ask your doctor about strategies to protect yourself from contracting the STD from your partner. For example, if your partner has HIV, your doctor will likely encourage you to take pre-exposure prophylaxis (PrEP).

If you’re eligible, you and your partner should also consider getting vaccinated for HPV and hepatitis B.

By following these strategies and others, you can lower your chances of getting STDs and passing them to others. Learn more about the importance of safe sex and STD prevention.

Don’t see what you need? Read our LGBTQIA safe sex guide.

If you test positive for an STD, it’s important to get treatment as soon as possible.

If you have one STD, it can often increase your chances of contracting another. Some STDs can also lead to severe consequences if left untreated. In rare cases, untreated STDs may even be fatal.

Fortunately, most STDs are highly treatable. In some cases, they can be cured entirely. In other cases, early and effective treatment can help relieve symptoms, lower your risk of complications, and protect sexual partners.

In addition to taking prescribed medications for STDs, your doctor may advise you to adjust your sexual habits to help protect yourself and others. For example, they’ll likely advise you to avoid sex altogether until your infection has been effectively treated. When you resume sex, they’ll probably encourage you to use condoms, dental dams, or other forms of protection.

Following your doctor’s recommended treatment and prevention plan can help improve your long-term outlook with STDs.