If you have sex — oral, anal or vaginal intercourse and genital touching — you can get an STD, also called a sexually transmitted infection (STI). Regardless of your marital status or sexual orientation, you're vulnerable to STIs and STI symptoms. Thinking or hoping your partner doesn't have an STI is no protection — you need to know for sure.
Condoms, when properly used, are highly effective for reducing transmission of some STDs. But no method is foolproof, and STI symptoms aren't always obvious. If you think you have STI symptoms or have been exposed to an STI, see a doctor. Also, inform your partner or partners so that they can be evaluated and treated.
Some STIs are easy to treat and cure; others require more-complicated treatment to manage them.
If untreated, STIs can increase your risk of acquiring another STI such as HIV. This happens because an STI can stimulate an immune response in the genital area or cause sores, either of which might raise the risk of HIV transmission. Some untreated STIs can also lead to infertility, organ damage, certain types of cancer or death.
Many STIs have no signs or symptoms (asymptomatic). Even with no symptoms, however, you can pass the infection to your sex partners. So it's important to use protection, such as a condom, during sex. And visit your doctor regularly for STI screening so you can identify and treat an infection before you can pass it on.
Chlamydia is a bacterial infection of your genital tract. Chlamydia may be difficult to detect because early-stage infections often cause few or no signs and symptoms. When they do occur, symptoms usually start one to three weeks after you've been exposed to chlamydia and may be mild and pass quickly.
Signs and symptoms may include:
- Painful urination
- Lower abdominal pain
- Vaginal discharge in women
- Discharge from the penis in men
- Pain during sexual intercourse in women
- Bleeding between periods in women
- Testicular pain in men
Gonorrhea is a bacterial infection of your genital tract. The bacteria can also grow in your mouth, throat, eyes and anus. The first gonorrhea symptoms generally appear within 10 days after exposure. However, some people may be infected for months before signs or symptoms occur.
Signs and symptoms of gonorrhea may include:
- Thick, cloudy or bloody discharge from the penis or vagina
- Pain or burning sensation when urinating
- Heavy menstrual bleeding or bleeding between periods
- Painful, swollen testicles
- Painful bowel movements
- Anal itching
Trichomoniasis is a common STI caused by a microscopic, one-celled parasite called Trichomonas vaginalis. This organism spreads during sexual intercourse with someone who already has the infection.
The organism usually infects the urinary tract in men, but often causes no symptoms. Trichomoniasis typically infects the vagina in women. When trichomoniasis causes symptoms, they may appear within five to 28 days of exposure and range from mild irritation to severe inflammation.
Signs and symptoms may include:
- Clear, white, greenish or yellowish vaginal discharge
- Discharge from the penis
- Strong vaginal odor
- Vaginal itching or irritation
- Itching or irritation inside the penis
- Pain during sexual intercourse
- Painful urination
HIV is an infection with the human immunodeficiency virus. HIV interferes with your body's ability to fight off viruses, bacteria and fungi that cause illness, and it can lead to AIDS, a chronic, life-threatening disease.
When first infected with HIV, you may have no symptoms. Some people develop a flu-like illness, usually two to six weeks after being infected. Still, the only way you know if you have HIV is to be tested.
Early signs and symptoms
Early HIV signs and symptoms usually disappear within a week to a month and are often mistaken for those of another viral infection. During this period, you're highly infectious. More-persistent or -severe symptoms of HIV
infection may not appear for 10 years or more after the initial infection. Early-stage HIV symptoms may include:
- Sore throat
- Swollen lymph glands
As the virus continues to multiply and destroy immune cells, you may develop mild infections or chronic signs and symptoms such as:
- Swollen lymph nodes — often one of the first signs of HIV infection
- Weight loss
- Cough and shortness of breath
Late-stage HIV infection
Signs and symptoms of late-stage HIV infection include:
- Persistent, unexplained fatigue
- Soaking night sweats
- Shaking chills or fever higher than 100.4 F (38 C) for several weeks
- Swelling of lymph nodes for more than three months
- Chronic diarrhea
- Persistent headaches
- Unusual, opportunistic infections
Genital herpes is a highly contagious STI caused by a type of the herpes simplex virus (HSV) that enters your body through small breaks in your skin or mucous membranes. Most people with HSV never know they have it, because they have no signs or symptoms or the signs and symptoms are so mild they go unnoticed.
When signs and symptoms are noticeable, the first episode is generally the worst. Some people never have a second episode. Others, however, can have recurrent episodes for decades.
When present, genital herpes signs and symptoms may include:
- Small red bumps, blisters (vesicles) or open sores (ulcers) in the genital and anal areas and areas nearby
- Pain or itching around the genital area, buttocks and inner thighs
Ulcers can make urination painful. You may also have pain and tenderness in your genital area until the infection clears. During an initial episode, you may have flu-like signs and symptoms, such as a headache, muscle aches and fever, as well as swollen lymph nodes in your groin.
In some cases, the infection can be active and contagious even when sores aren't present.
HPV infection is one of the most common types of STIs. Some forms of HPV put women at high risk of cervical cancer. Other forms cause genital warts. HPV usually has no signs or symptoms. The signs and symptoms of genital warts include:
- Small, flesh-colored or gray swellings in your genital area
- Several warts close together that take on a cauliflower shape
- Itching or discomfort in your genital area
- Bleeding with intercourse
Often, however, genital warts cause no symptoms. Genital warts may be as small as 1 millimeter in diameter or may multiply into large clusters. Warts can also develop in the mouth or throat of a person who has had oral sex with an infected person.
Hepatitis A, hepatitis B and hepatitis C are all contagious viral infections that affect your liver. Hepatitis B and C are the most serious of the three, but each can cause your liver to become inflamed.
Some people never develop signs or symptoms. But for those who do, signs and symptoms may occur several weeks after exposure and may include:
- Nausea and vomiting
- Abdominal pain or discomfort, especially in the area of your liver on your right side beneath your lower ribs
- Loss of appetite
- Dark urine
- Muscle or joint pain
- Yellowing of your skin and the whites of your eyes (jaundice)
Syphilis is a bacterial infection. The disease affects your genitals, skin and mucous membranes, but it can also involve many other parts of your body, including your brain and your heart.
The signs and symptoms of syphilis may occur in three stages — primary, secondary, and tertiary. Some people also experience latent syphilis, in which blood tests are positive for the bacteria but no symptoms are present.
At first, only a small, painless sore (chancre) may be present at the site of infection, usually the genitals, rectum, tongue or lips. As the disease worsens, symptoms may include:
- Rash marked by red or reddish-brown, penny-sized sores over any area of your body, including your palms and soles
- Enlarged lymph nodes
- Fatigue and a vague feeling of discomfort
- Soreness and aching
Without treatment, syphilis bacteria may spread, leading to serious internal organ damage and death years after the original infection.
Some of the signs and symptoms of late-stage syphilis include:
- Lack of coordination
There's also a condition known as congenital syphilis, which occurs when a pregnant woman with syphilis passes the disease to her unborn infant. Congenital syphilis can be disabling, even life-threatening, so it's important for pregnant women with syphilis to be treated.
At any stage, syphilis can affect the nervous system. Neurosyphilis may cause no signs or symptoms, or it can cause:
- Behavior changes
- Movement problems
If you suspect that you have these or other STIs or that you may have been exposed to one, see your doctor for testing. Timely diagnosis and treatment is important to avoid or delay more-severe, potentially life-threatening health problems and to avoid infecting others.
April 30, 2020
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- Magowan BA, et al., eds. Pelvic infection and STIs. In: Clinical Obstetrics & Gynaecology. 4th ed. Elsevier; 2019. https://www.clinicalkey.com. Accessed April 13, 2020.
- Sexually transmitted infections (STIs). World Health Organization. https://www.who.int/en/news-room/fact-sheets/detail/sexually-transmitted-infections-(stis). Accessed April 13, 2020.
- Symptoms of HIV. HIV.gov. https://www.hiv.gov/hiv-basics/overview/about-hiv-and-aids/symptoms-of-hiv. Accessed April 14, 2020.
- What is viral hepatitis? Centers for Disease Control and Prevention. https://www.cdc.gov/hepatitis/abc/index.htm. Accessed April 14, 2020.