Sexually Transmitted Diseases (STDs)

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What are sexually transmitted diseases?

Sexually transmitted diseases (STDs) are infections passed from one person to another during sexual contact. Sexually transmitted infection, or STI is another term for STD. Some STDs can also be passed to another person through other means, such as through blood transfusions or from an infected mother to her baby during pregnancy or childbirth.

STDs are very common, especially among young people ages 15 to 24. There are an estimated 26 million new STD infections every year, with about 68 million people living with an STD (1 in 5 people in the United States) “on any given day,” according to the Centers for Disease Control and Prevention. For gonorrhea, chlamydia and syphilis alone, there were 2.6 million new cases reported in the United States in 2019. Increases in syphilis cases from 2015 to 2019 are due, in part, to newborns contracting it from an infected mother during childbirth.

Most STDs are highly preventable. If diagnosed early, some STDs, such as gonorrhea and chlamydia, can be quickly and easily treated and cured before serious complications develop.

Other STDs, such as HIV/AIDS and genital herpes, are not curable, but prompt diagnosis and treatment can help reduce or delay the onset of serious complications and minimize the spread of the disease to others.

Any person who engages in sexual activity can contract and pass on an STD. This includes heterosexual, homosexual, and bisexual men and women.

Untreated STDs can lead to serious complications, such as pelvic inflammatory disease, opportunistic infections, and complications in newborns. Using safer sex practices, seeking regular medical care, and seeking early, regular prenatal care can help reduce the risk of serious complications of STDs.

What are the different types of STDs?

Bacteria, viruses, parasites—at least 35 different organisms—cause sexually transmitted diseases. The STD list includes:

  • Chancroid, bacterial infection caused by Haemophilus ducreyi
  • Chlamydia, bacterial infection caused by Chlamydia trachomatis, and one of the most commonly reported STDs 
  • Genital herpes, caused by herpes simplex virus type 1 or 2 
  • Genital warts, caused by human papillomavirus (HPV)
  • Gonorrhea, bacterial infection caused by Neisseria gonorrhoeae. It is one of the most common STDs, but it seldom causes symptoms so cases are not diagnosed.   

     

  • Hepatitis, caused by hepatitis viruses A, B and C
  • HIV/AIDS, caused by human immunodeficiency virus
  • Pubic lice (crabs), an infestation of pubic hair by a parasitic insect
  • Scabies, an infestation of the skin by an itch mite, Sarcoptes scabiei var. hominis
  • Syphilis, a bacterial infection caused by Treponema pallidum
  • Trichomoniasis, a parasitic infection caused by Trichomonas vaginalis

What are the symptoms of STDs?

Symptoms of STDs vary depending on the type of STD and the individual case. Some STDs have no symptoms early in the disease, and some never generate symptoms. However, serious permanent damage to the reproductive tissues, infertility, and other complications can occur even when no symptoms are present.

Genital and reproductive organ symptoms

Symptoms that affect the genitals and reproductive organs include:

  • Anal pain, itching or bleeding

  • Blisters and sores on the genital

  • Burning with urination

  • Infertility

  • Pain with sexual intercourse

  • Pelvic pain

  • Pubic itching

  • Pubic rashes

  • Testicular pain

  • Thick discharge from the penis

  • Unusual vaginal discharge or vaginal discharge with a foul odor

Other STD symptoms

Some STDs, such as HIV/AIDS and syphilis, can cause symptoms in other body systems outside the reproductive system and genitals. These symptoms include:

What causes STDs?

STDs are caused by infections of certain organisms:

  • Bacteria cause chancroid, chlamydia, bacterial vaginosis, and syphilis.

  • Viruses cause hepatitis, herpes, HIV/AIDS, and genital warts (HPV).

  • Parasites cause pubic lice (crabs), scabies, and trichomoniasis.

  • Yeast causes vaginal yeast infections, yeast infections of the top of the penis, and yeast infections of the mouth.

Infections that cause STDs are passed from one person to another during sexual contact. This includes vaginal, oral, or anal sex. Any person who engages in sexual activity can contract and pass on an STD, including heterosexual, homosexual, and bisexual men and women. STDs rarely occur in isolation. Multiple infections are often diagnosed, such as HPV and chlamydia. Also, the presence of one STD predisposes the individual to additional infections; for example, herpes lesions and syphilis or HPV warts and increased HIV risk.

In addition, some STDs can be passed to another person through other means, such as through blood transfusions, through contaminated needles, or from an infected mother to her baby during pregnancy or childbirth.

What are the risk factors for STDs?

Risk factors for STDs include:

  • Being a man who has sex with a man

  • Being born to and/or breastfed by a mother with an STD

  • Having had a transfusion of blood products before 1985 

  • Having certain infectious diseases, such as tuberculosis and hepatitis

  • Having HIV/AIDS or any type of STD, which increases the risk of STDs in general

  • Having multiple sexual partners (the more sexual partners a person has, the greater the risk of catching STDs)

  • Having sex for money or drugs

  • Having unprotected sex, including vaginal, oral, or anal sex, with a partner who has had one or more other sexual partners

  • Sharing contaminated needles to inject drugs or for tattooing

How do you prevent STDs?

Catching and passing on sexually transmitted infection is preventable. It is important to understand that it is possible to transmit an STD even when there are no symptoms.

You can lower your risk of STDs by:

  • Abstaining from sexual activity

  • Engaging in sexual activities only within a mutually monogamous relationship in which neither partner is infected with STDs or has risk factors for infection

  • For injectable drug use, using a sterile, unused needle for each injection

  • For tattooing, avoiding tattoo parlors that use pooled inks and using a sterile, unused needle for each act of tattooing

  • Getting regular, routine medical care that includes testing for common STDs

  • Getting the human papillomavirus vaccine and hepatitis B vaccine

  • Reducing the number of sex partners you have

  • Seeking medical care as soon as possible after possible exposure to STDs or after high-risk sexual activity

  • Seeking prenatal care early and regularly during a pregnancy

  • Using a new condom for each sex act

How do doctors diagnose STDs?

Seek medical care as soon as possible after possible exposure to an STD or after engaging in high-risk sexual activity. Tests used to diagnose STDs depend on the type of STD, but include simple blood tests or testing a sample of cells or a sore for the presence of the bacteria, virus or other organism.

STD testing options:

  • Chlamydia is diagnosed by testing a small sample of cells or discharge taken from a woman’s cervix or a man’s urethra.

  • Genital herpes is diagnosed by testing a small sample of cells or drainage taken from the suspected herpes blister or lesion. A blood test may also be performed to test for the specific antibodies that are produced by the immune system in response to a genital herpes infection.

  • Gonorrhea is diagnosed by testing a small sample of cells or discharge taken from a woman’s cervix or a man’s urethra.

  • HIV is diagnosed with a blood or oral swab test that can reveal the presence of the specific antibodies the body makes in response to the HIV infection. With these techniques, HIV may not be detectable in the first 1 to 3 months after infection, and a series of tests may be necessary to diagnose or rule out HIV infection. 

  • HPV (human papillomavirus), which causes genital warts and several types of cancer, requires a sample of cells from a visible wart or, in females, the cervix (via Pap smear) for diagnosis.

  • Syphilis is diagnosed by a simple blood test.

  • Vaginitis is diagnosed by taking small samples of cells from the vagina and cervix for culture and sensitivity testing. Various tests on the samples are performed to determine if a bacteria, fungus or parasite is causing the infection and to determine the most effective medication to treat it. If an allergy is suspected to be causing the vaginitis, diagnostic testing may include allergy testing, called skin patch testing.

Know your STD status: If you are sexually active or plan to have sex, consider asking a healthcare provider about getting tested for STDs. Testing and screening recommendations vary by infection, age and sex.

Pregnant women, in particular, should get tested for HIV, hepatitis B, and syphilis. Pregnant women at risk for STDs should also be tested for chlamydia and gonorrhea.

How are STDs treated?

Some STDs, such as chlamydia, gonorrhea and syphilis, are easily curable in their early stages. Prompt diagnosis and treatment can eliminate the risk of developing serious complications.

Certain STDs, such as genital herpes, HIV/AIDS and HPV, are not curable, but prompt diagnosis and treatment can reduce or delay the onset of serious complications, improve quality of life, and minimize the spread of the disease to others. An HPV vaccine is recommended for people ages 11 and older.

Treatment plans vary depending on the type and stage of the STD and other factors:

  • STDs caused by a bacterial infection, such as chlamydia, gonorrhea or syphilis, or by the parasite Trichomonas are treated with oral antibiotic medication. Gonorrhea has developed resistance to most antibiotics, which makes prevention even more important for this disease. Syphilis and chancroid bacteria are also developing resistance.

  • Pubic lice are treated with an appropriate topical medication that contains a pesticide.

  • STDs caused by certain viruses, such as HIV/AIDS and genital herpes, are not curable, but they can be controlled to various degrees with antiviral or antiretroviral medications.

  • Genital warts may be treated by topical medication or by cryotherapy, which destroys them by freezing. However, removing genital warts does not cure the body of human papillomavirus (HPV). 

For all types of STDs, it is important to abstain from sexual activity until the infection is cured and/or a healthcare provider has cleared you to have sex, and your sexual partner(s) have been fully treated, regardless if symptoms are present.

It is important to discuss any infection with your sexual partner(s), no matter how difficult it is to do so.

How does an STD affect quality of life?

Both treated and untreated sexually transmitted diseases can result in lifelong consequences. Based on quality of life questionnaires completed by women diagnosed with either human papillomavirus (HPV), chlamydia, or trichomoniasis, shame and low self-esteem were linked with low quality of life. How long the disease lasted had a significant and negative impact on quality of life, reducing the ability to function in everyday life. The psychological effect of fear of STD complications, mainly HPV-related cancer, is associated with depression. The women also reported frustration, anxiety, anger, isolation and guilt.

About 40% of individuals living in the U.K. or Greece with a chronic STD, such as HIV, HPV, or genital herpes experienced low mood and depression symptoms, based on a quality of life questionnaire. Study participants also reported lower quality of life and values for:

  • Physical safety

  • Quality and accessible healthcare

  • Recreational and social activities 

Public health concerns

In addition to the personal burdens, STDs are a major public health concern due to the cost of treating the diseases and STD complications, such as infertility, cancer, mental illness, and fetal health problems.

Factors that complicate the burden of STDs include:

  • Drug abuse. This can lead to high-risk sexual behavior, which increases the risk of STDs.

  • Healthcare access. Marginalized populations tend to experience reduced access to healthcare, which, in turn, reduces available screening, prevention and treatment of STDs.

  • Income. STD rates are higher in disadvantaged populations.

  • Race and ethnicity. These infections are more common in Black Americans, Hispanic, and American Indian/Alaska Native populations than in non-Hispanic Caucasians.

  • Social stigma. The secrecy and shame associated with STDs in the United States reduces diagnosis and increases spread to others.

What are the potential complications of STDs?

Complications of untreated STDs can be serious and life-threatening. You can minimize the risk of serious complications for yourself, your unborn child, and your sexual partner(s) by following the treatment plan you and your healthcare professional design specifically for you.

Left untreated, STDs can lead to serious complications including:

  • An increased risk for contracting HIV, which causes AIDS

  • An increased risk for contracting other STDs

  • Blindness

  • Cancer, including cervical, throat and anal cancer

  • Dementia

  • Frequent serious, opportunistic infections

  • Infertility (every year, as many as 24,000 females may become infertile due to an STD)

  • Pelvic inflammatory disease

  • Pelvic abscess

  • Prematurity, birth defects, and stillbirth

Do STDs shorten life expectancy?

The true number of deaths due to sexually transmitted infections is difficult to determine because it may occur many years after the symptomatic stage of disease. Cervical and other cancers caused by some types of human papillomavirus can be fatal decades after initial infection, as can HIV progression to AIDS. Untreated STDs can lead to other serious complications, such as pelvic inflammatory disease (which can be fatal), infertility, other STDs, and opportunistic infections.

Syphilis can be a direct cause of death in adults as well as children born to infected mothers. Today, adult deaths due to syphilis are very rare and infant deaths are not as common in the U.S. as they are worldwide. Globally, syphilis in pregnancy causes more than 300,000 fetal and newborn deaths every year.

Screening and treatment of STDs reduces the risk of death and complications that can shorten life expectancy. Some sexually transmitted diseases, even syphilis, are easily treated and cured with antibacterial and other drugs, and have an excellent prognosis. Early diagnosis and treatment of HIV infection with daily medication can delay the development of AIDS by decades. Human papillomavirus (HPV) infection is a risk factor for cancer, but only certain types of HPV cause cancer and there are other risk factors. Getting vaccinated against HPV prevents infection and reduces the risk of associated cancers.

STD awareness

According to a 2018 poll by the Kaiser Family Foundation, only 13% of people know that more than 50% of the population will get an STD during their lifetime. A smaller percent are worried about contracting one, even as STD rates are rising year after year.

Interestingly, the COVID-19 pandemic has cast a brighter light on the inequalities of health and social care for minority groups at increased risk of infection, including sexually transmitted infections. To begin to address the racial, gender and social disparities and blunt rising STD rates, public health strategies to increase access to sexual health services could include setting up walk-in STD testing sites (without a full medical exam) and partnering with retail pharmacies to offer STD testing and treatment.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 Jun 2
THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
  1. Sexually Transmitted Diseases (STDs). Centers for Disease Control and Prevention. https://www.cdc.gov/std/ 
  2. Sexually Transmitted Disease Surveillance 2019. https://www.cdc.gov/std/statistics/2019/default.htm
  3. Collins RD. Differential Diagnosis and Treatment in Primary Care, 6th ed. Philadelphia: Wolters Kluwer, 2018.
  4. Kellerman RD, Raker DP (Eds.) Conn’s Current Therapy, 72d ed. Philadelphia: Elsevier, 2020.
  5. CDC estimates 1 in 5 people in the U.S. have a sexually transmitted infection. Centers for Disease Control and Prevention. https://www.cdc.gov/media/releases/2021/p0125-sexualy-transmitted-infection.html 
  6. Sexually Transmitted Diseases. HealthyPeople.gov https://www.healthypeople.gov/2020/topics-objectives/topic/sexually-transmitted-diseases 
  7. Passanisi A, Leanza V, Leanza G. The impact of sexually transmitted diseases on quality of life: Application of three validated measures. Giornale Italiano di Ostetricia e Ginecologia. 2013;35(6):722-727. Abstract retrieved from https://www.researchgate.net/publication/286165338_The_impact_of_sexually_transmitted_diseases_on_quality_of_life_Application_of_three_validated_measures    
  8. Ginieri-Coccossis M, Triantafillou E, Papanikolaou N, et al. Quality of life and depression in chronic sexually transmitted infections in UK and Greece: The use of WHOQOL-HIV/STI BREF. Psychiatriki. 2018;29(3):209-219. doi:10.22365/jpsych.2018.293.209. Retrieved from https://pubmed.ncbi.nlm.nih.gov/30605425/ 
  9. KFF Poll: Most Americans Are Unaware of How Common STIs Are Among Adults and That Rates Are Rising. Kaiser Family Foundation. https://www.kff.org/womens-health-policy/press-release/kff-poll-most-americans-are-unaware-of-how-common-stis-are-among-adults-and-that-rates-are-rising/ 
  10. Sexually transmitted infections (STIs). World Health Organization. https://www.who.int/news-room/fact-sheets/detail/sexually-transmitted-infections-(stis) 
  11. Peterman TA, Kidd SE. Trends in Deaths Due to Syphilis, United States, 1968-2015. Sex Transm Dis. 2019;46(1):37-40. doi:10.1097/OLQ.0000000000000899. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6743072/