Sexually Transmitted Diseases

Sexually transmitted diseases (STDs) are infections that pass from one person to another through sexual contact, which includes oral, genital, or anal intercourse.

What Are STDs?

STDs can be caused by bacteria, viruses, or parasites. Although the symptoms of a particular STD depend on the specific infection, many STDs cause vaginitis (vah-jih-NYE-tis), an inflammation of the vagina often accompanied by an abnormal discharge (fluid released from the body), and urethritis (yoo-ree-THRY-tis), an inflammation of the urethra (the tube through which urine passes from the bladder to the outside of the body), which can make urination painful. Several STDs can produce blisters or sores on the penis, vagina, rectum, or buttocks. In women, some STDs may spread to the cervix ^* , a condition called cervicitis (sir-vih-SYE-tis), or to the uterus ^* and fallopian tubes ^* , a condition known as pelvic inflammatory disease (PID). In men STDs may spread to the testicle (causing epididymitis ^* ) or prostate ^* (causing prostatitis, inflammation of the prostate). It is not uncommon for several STDs to occur in the same person, and the presence of an STD can increase the risk of contracting infection with human immunodeficiency (ih-myoo-no-dih-FIH-shen-see) virus (HIV), the virus that causes acquired immunodeficiency syndrome (AIDS), from an infected partner.

How Common Are They?

STDs are common in the United States; between 13 million and 15 million new cases are diagnosed every year. Despite the fact that much information is available about preventing these infections and limiting their spread, the number of people infected is growing, and about two-thirds of cases are reported in people under the age of 25 years.

Are STDs Contagious?

STDs are contagious and are transmitted through sexual contact that involves vaginal, anal, or oral sex. The diseases can spread between people of the opposite sex or people of the same sex. The germs that cause many STDs move from person to person through semen (the sperm-containing whitish fluid produced by the male reproductive tract), vaginal (VAH-jih-nul) fluids, or blood. Other STDs, like herpes and genital warts, can spread by intimate skin-to-skin contact, often with sores the disease causes. Certain STDs can pass from a mother to her baby during pregnancy or childbirth. STDs do not pass from one person to another by simply hugging, shaking hands, or sharing utensils.

What Are Some Common STDs?

Gonorrhea

Gonorrhea (gah-nuh-REE-uh) is caused by the bacterium Neisseria gonorrhoeae (nye-SEER-e-uh gah-no-REE-eye). It may not produce any symptoms in women who are infected. When symptoms are present, they include vaginal discharge and pain when urinating. Lower belly pain usually occurs when the infection has spread past the cervix and caused PID. Most men with gonorrhea have a discharge from the penis and pain when they urinate. Gonorrhea is treated with antibiotics that kill the bacteria.

Syphilis

Syphilis (SIH-fih-lis) is caused by the bacterium Treponema pallidum (treh-puh-NEE-muh PAL-ih-dum). It is different from many other STDs, because there are distinct stages to the illness. In the first stage, a small, hard sore called a chancre (SHANG-ker) appears where the bacteria entered the body. In the next stage, a red or brown rash develops, sometimes on the palms of the hands and soles of the feet; in some cases, patients also may have a fever, swollen lymph nodes ^* , muscle aches, and headaches. If the disease goes untreated, it can progress to the third and most serious stage, when it may damage the bones, organs, and nervous system, which can result in blindness, paralysis ^* , dementia ^* , heart problems, and sometimes even death. Like gonorrhea, syphilis can be treated effectively with antibiotics. More than 31,000 cases of syphilis were reported in the United States in 2000.

Herpes simplex virus

Herpes simplex (HER-peez SIM-plex) virus causes herpes. There are two types of herpes, type 1 and type 2. Type 2 usually spreads through sexual contact and causes genital herpes. In a person with genital herpes, small, painful blisters develop on the vagina, cervix, penis, buttocks, or thighs. Once infection occurs, the herpes virus remains in the body and can recur throughout a person's life. Antiviral medications may shorten outbreaks of symptoms and make them less severe, but they do not kill the virus. In the United States an estimated 45 million people over the age of 12 have genital herpes infection.

Chlamydia

Chlamydia (kla-MIH-dee-uh) is caused by the bacterium Chlamydia trachomatis (kla-MIH-dee-uh truh-KO-mah-tis), and in many infected people it produces no symptoms. The most common symptoms in both men and women are discharge and pain when urinating. Because infection with chlamydia may not be noticed, it can spread and produce other symptoms, including epididymitis in men and PID in women. More than 700,000 cases were reported in the United States in 2000, but the actual number of new cases could be 3 million to 4 million per year. A person with chlamydia can be treated effectively with antibiotics.

HIV

Infection with HIV damages immune system cells in the body that normally fight infections, leaving the body unable to defend itself against a variety of illnesses. A person can be infected with HIV and not have AIDS, although most people with HIV do end up developing AIDS. The first symptoms of HIV infection include fever, muscle aches, sore throat, and, in some cases, a rash that looks somewhat like that of measles ^* . Other symptoms usually take much longer to appear, perhaps years, and may include rapid weight loss, recurring fever, a dry cough, night sweats, pneumonia ^* , white spots on the tongue or throat, long-lasting diarrhea, and skin rashes and yeast infections. A person with AIDS also may have memory loss, depression, and extreme tiredness.

Human papillomavirus, or HPV, of which there are over 50 types. HPV causes genital warts and is strongly associated with cervical and penile cancers.

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In the United States, there were more than 40,000 new cases of AIDS reported in 2000, and more than 850,000 people were living with HIV in 2000. There have been more than 460,000 reported deaths related to AIDS in the United States since the disease was first identified in the early 1980s. There is no cure for AIDS, but a combination of medications can help a person live longer and have a better quality of life.

Human papillomavirus

Genital and anal warts are caused by human papillomavirus (pah-pih-LO-mah-vy-rus), or HPV, a very common virus. The warts are soft and skin-colored, and they can grow alone or in bunches on the genitals; on the skin around the genitals, rectum, or buttocks; or in the vagina or cervix. Like herpes, genital warts can reappear again and again, because once this type of virus enters the body, it remains there for life. Doctors can remove genital warts by freezing, burning, or cutting them off or by coating them with medication that destroys the warts. In women, infection with HPV can affect the cells of the cervix, which may lead to cervical cancer.

Trichomoniasis

Trichomoniasis (trih-ko-mo-NYE-uh-sis) is a very common STD that is caused by a parasite. Most women with trichomoniasis have a frothy, yellow, foul-smelling vaginal discharge, along with itching and irritation in the vagina and discomfort during sex and urination. Men with this STD typically do not have symptoms; those who do have symptoms may feel irritation in the penis or a burning sensation after they urinate or ejaculate ^* . More than 2 million cases are diagnosed each year in the United States. Trichomoniasis can be treated with antibiotics.

Can STDs Be Prevented?

The only sure way to prevent STDs is not to have sexual contact with anyone. In most cases, it is impossible or very difficult to tell whether another person has an STD. People may not always tell the truth about their sexual past, or they may have an STD and not know it. For people who do have sex, the safest choices are to limit the number of sexual partners and to use latex condoms. Latex condoms lower the risk of contracting many STDs, including HIV infection. Certain STDs such as genital warts and herpes may present additional problems, because the warts or herpes blisters can be on the skin around the genitals and condoms do not protect against them if the sores are not covered by the condom. Avoiding skin-to-skin contact is the best option for preventing these kinds of STDs.