Sexually Transmitted Diseases (STDs)

Sexually transmitted diseases (STDs), also called venereal diseases (VD), are illnesses that are contracted by having sexual contact—vaginal, oral, or anal sex—with someone who already has the disease. Because it is possible to transmit an STD without having any symptoms, the term sexually transmitted infections (STIs) is increasingly used to include the infections that are transmitted without signs of the disease. It is possible to transmit some STIs by intravenous drug use, as well as through childbirth or breastfeeding.

According to the Centers for Disease Control (CDC), approximately 19 million new STD infections occur each year; roughly half of them among young people aged 15 to 24 years. While substantial progress has been made in preventing, diagnosing, and treating STDs in recent years, these infections remain a major public health challenge in the United States. In addition, it is estimated that STDs result in up to $14.7 billion in direct medical costs annually. ^[1]

Types

Keratotic Lesions on the Palms Due to Secondary Syphilis. Source: Centers For Disease Control, Public Health Image Library.

Researchers have identified more than 20 different kinds of STDs:

STDs caused by bacteria

These diseases can be treated and often cured with antibiotics.

• Chlamydia infection—Caused by Chlamydia trachomatis.
• Gonorrhea infection—Caused by Neisseria gonorrheae. Also known as "the clap."
• Syphilis—Caused by Treponema pallidum.
• Chancroid—Caused by Haemophilus ducreyi.
• Donovanosis—Caused by Calymmatobacterium granulomatosis. Also known as granuloma inguinale.
• Lymphogranuloma venereum—Caused by Chlamydia trachomatis.
• Nongonococcal urethritis—Caused by Ureaplasma urealyticum or Mycoplasma hominis.

STDs caused by viruses

Herpes simplex type I sores. Source: CDC.

These diseases can be controlled, but not cured. Once someone is infected with a viral STD, they will probably always carry it. They are not always infectious, however.

• HIV/AIDS—Caused by the human immunodeficiency virus.
• Genital herpes—Caused by herpes simplex virus.
• Human Papillomavirus and Genital Warts—Caused by human papilloma virus.
• Hepatitis B—Caused by hepatitis B virus.
• Cytomegalovirus (CMV)—Caused by CMV, a genus of the herpesvirus group and transmitted through saliva and skin-to-skin contact in addition to sexual contact.
• Molluscum (MC)—Caused by a DNA poxvirus called the molluscum contagiosum virus.
• Mononucleosis—Caused by the Epstein-Barr virus, spread through saliva or through sex.

STDs caused by fungi

• Tinea Cruris (Jock Itch)—Caused by a variety of types of fungi.
• Yeast Infection—Caused by any of the Candida species, of which Candida albicans is the most common.

STDs caused by parasites

These can usually be treated with a drug that kills the parasite.

• Pubic lice—Caused by Phthirius pubis. Also known as "crabs."
• Scabies—Caused by Sarcoptes scabiei. Can also be transmitted by non-sexual contact.

STDs caused by protozoa

This can usually be treated by antiprotozoal drugs, such as Metronidazole.

• Trichomoniasis—Caused by Trichomonas vaginalis.

Signs and Symptoms

Many STDs can be asymptomatic. The symptoms vary among the different types of STDs. Some common symptoms include:

• Unusual discharge from the penis or vagina

• Sores or warts on the genital area

• Burning while urinating

• Itching and redness in the genital area

• Anal itching, soreness, or bleeding

• Mild fevers, joint aches, and muscle aches

Causes

STDs are caused by infectious organisms—bacteria, viruses, parasites, and protozoa. They are transmitted by sexual contact and may be transmitted by sharing blood or bodily fluids such as semen or saliva with a person infected with an STD. Different STDs have different ways of being transmitted between people.

Diagnosis

Gram stain of N. gonorrhoeae from a patient with acute gonorrhea. Source: CDC.

STDs can be diagnosed by:

• bacterial cultures (for bacteria), tissue culture (for viruses) of infected bodily fluids or tissue
• tests that detect an immune response to the infecting agent (Western Blot for HIV, RPR for syphillis)
• molecular tests that detect the DNA or RNA (genes) of the infecting agent.

If a person has one STD, they are at risk for additional STDs. If testing is being performed for one test, such as gonorrhea, it should also be performed for other STDs that may not be showing symptoms yet, such as chlamydia, HIV/AIDS, and hepatitis B.

Treatment

Many STDs can be treated with medication. Bacterial STDs such as gonorrhea or chlamydia can usually be treated with a single dose of antibiotics. Viral STDs, such as herpes, are incurable and often require treatments that are taken at the time of an outbreak or on a regular basis to help prevent outbreaks. Treatment may be in the form of pills or ointments applied to the lesions.

Prevention

STDs can be prevented by avoiding sexual contact, by avoiding injection of drugs, and by practicing "safe sex." This means:

• Practicing monogamy with a partner who does not have STDs

• Consistently using a condom for vaginal, oral, and anal intercourse

• Knowing a partner and his/her STD status and health

• Having regular medical check-ups, especially with a history of more than one sexual partner

Related Problems

Some STDs have long-term consequences.

Infections with gonorrhea or chlamydia can cause pelvic inflammatory disease in women, which can lead to infertility.

Untreated syphilis can lead to long-term neurologic problems.

Urethral infections in men, such as gonorrhea or chlamydia, can lead to urethral stricture disease.

Certain types of human papilloma virus infections are associated with cervical cancer. Research suggests that only 10% of infected women develop a type of infection that can lead to cancer, and that only a much smaller percentage of these women will go on to develop cervical cancer years later.^[2]

Public Health

According to the CDC, chlamydia is the most common STD. In 2006, 1,030,911 chlamydial infections were reported to CDC from 50 states and the District of Columbia. Gonorrhea is the second most frequently reported STD.^[3]

Coping with STDs

Many people have a hard time coping when they learn they have an STD. Feelings may include anger at the person from whom the disease was contracted, regret over the episode that led to contracting the STD, fear about potential future health problems and future relationships, and embarrassment over having a contagious disease that is spread by sexual contact. The intensity of the response varies when someone is diagnosed with a curable (bacterial) versus an incurable (viral) STD.

Tips

• Persons diagnosed with an STD should avoid having unprotected intercourse, especially right after the diagnosis and before treatment has begun.
• Support groups can be great resources for learning of treatment options and for emotional support.
• Looking at the positive aspects of illness is often very helpful. Illness is sometimes all a person needs to make positive lifestyle changes and begin to enjoy life more fully and in more meaningful ways.

Resources

• Yahoo! Health: STDs—Stages of Coping
• Strategies for Coping with Sexually Transmitted Diseases by Adolescent Females
• Coping with STDs
• STD Support Web site
• MedHelp.org: STD Support

References

1. ↑ Centers for Disease Control and Prevention. Trends in reportable sexually transmitted diseases in the United States, 2006.
2. ↑ Schiffman M, Castle PE, Jeronimo J, Rodriguez AC, Wacholder S. Human papillomavirus and cervical cancer. Lancet. 2007 Sep 8;370(9590):890-907. Abstract
3. ↑ Centers for Disease Control and Prevention. STD Surveillance 2006

External Links

National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention

STD Organization With Free Clinic Finder in the US

CDC: Sexually Transmitted Disease Information