What are sexually transmitted diseases (STDs)?

Sexually transmitted diseases, commonly called STDs, are also known as sexually transmitted infections (STIs). You can get an STD from any kind of sexual activity that involves the mouth, anus, vagina or penis.

STDs are serious illnesses that need treatment. Some, like the human immunodeficiency virus (HIV), cannot be cured and can be life-threatening without treatment.

What are the types of STDs?

Some sexually transmitted infections include:

Who is at risk for an STD?

Anyone who is sexually active is at risk for an STD. Drug use and using other substances can increase the likelihood of catching an STD. Shared needles can spread STDs. Also, if you’re high, you’re less likely to practice safe sex.

Secrecy around sexuality also raises the risk. People who feel stigma (shame or embarrassment) about STDs may be less likely to seek treatment. They may not want to tell anyone they have an STD. But without treatment, people keeping spreading the STD to others. Being open about your symptoms and sexual history is important for the health and well-being of you and your partners.

How common are STDs?

Every year, around 20 million new STD infections occur. About half of them happen to people ages 15 to 24. Gonorrhea, chlamydia and syphilis are the most commonly discussed STDs and syphilis in pregnancy may lead to congenital syphilis if left untreated.

What's expedited partner therapy?

Expedited partner therapy (EPT) is where your healthcare provider gives you a prescription for your partner without examining the partner when you’re diagnosed with chlamydia or gonorrhea. Typically the healthcare provider would wait to examine a patient before providing a prescription, but the logical assumption is that if you have the STD, then your partner probably does as well. This prevents reinfection and stops additional transmission as soon as possible.

What causes an STD?

STDs develop when various bacteria, viruses or parasites infect your body. People share these microorganisms through bodily fluids during sexual activity — usually vaginal, oral or anal sex. STDs like syphilis can be transmitted to an unborn child

Some STDs may be present in infected blood. People who share infected drug needles can pass on STDs.

What are STD symptoms?

You might not have any symptoms with an STD. Get tested regularly if you are sexually active. You can have (and pass on) an STD without even knowing it. The CDC recommends a gonorrhea and chlamydia screen for people younger than 25.

If you do have symptoms, they may include:

Genital symptoms: (Some patients may be asymptomatic.)

  • Bumps, sores or warts on or near the penis, vagina, mouth or anus.
  • Swelling, redness or severe itching near the penis or vagina.
  • Discharge from the penis.
  • Vaginal discharge that has a bad odor, causes irritation or is a different color or amount than usual.
  • Vaginal bleeding that’s not your period.
  • Painful sex.

Other symptoms:

  • Skin rash.
  • Weight loss, diarrhea, night sweats.
  • Aches, pains, fever and chills.
  • Jaundice (yellowing of the skin and whites of the eyes).
  • Painful urination or frequent urination.

Is an STD contagious?

Yes, if you have an STD, you can pass it on through sexual contact. That’s why it’s important to see a healthcare provider and get treatment right away. Once the STD goes away, you can resume your sex life.

You don’t have to worry about passing an STD through casual contact. Shaking hands or sharing a bathroom won’t lead to STDs.

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