Sexually Transmitted Infections

B

Gonorrhea

Gonorrhea, caused by the bacterium Neisseria gonorrhoeae, infects the membranes lining certain genital organs. Although roughly 360,000 gonorrhea infections are reported each year in the United States, experts estimate that closer to 650,000 people are infected annually. Like chlamydia, gonorrhea is often symptomless. When present, symptoms may be similar to those of chlamydia and include burning urination and penile or vaginal discharge. Untreated gonorrhea can cause PID in women. Babies born to mothers with gonorrhea are at risk of infection during childbirth; such infections can cause eye disease in the newborn. Physicians diagnose gonorrhea by testing penile or vaginal discharge or urine specimens for the presence of Neisseria gonorrhoeae. Gonorrhea is treatable with several antibiotics, although the infection has become resistant to treatment with some drugs in the past several decades.

C

Syphilis

Syphilis, a potentially life-threatening STI, is caused by the bacterium Treponema pallidum. According to the CDC, there are an estimated 36,000 new cases of syphilis in the United States each year. In the early stage of syphilis, a genital sore, called a chancre, develops shortly after infection and eventually disappears on its own. If the disease is not treated, the infection can progress over years, affecting the vertebrae, brain, and heart, and resulting in such varied disorders as lack of coordination, meningitis, and stroke. Syphilis during pregnancy can be devastating to the fetus, causing deformity and death, and most pregnant women in the United States receive screening for the disease in the first weeks of pregnancy so that the disease can be treated before the fetus is harmed. Syphilis is easily treated with penicillin, and the number of cases in the United States has dropped considerably since 1982. By the late 1990s, however, many urban communities experienced a resurgence in syphilis cases among men who have sex with men.

D

Genital Herpes

Genital herpes is caused by infection with the herpes simplex virus (HSV). Most cases of genital herpes are due to HSV type 2. Some cases, however, result from genital infections with HSV type 1, a common cause of cold sores. Genital herpes causes recurrent outbreaks of painful sores on the genitals, although the disease often remains dormant with no symptoms for long periods. In the United States, one in five individuals over the age of 12 is infected with HSV type 2, and the vast majority of those infected—about 90 percent—do not know they have the disease. Blood tests can detect HSV infection, even if a person has no symptoms. The symptoms of HSV can be treated with antiviral drugs, such as acyclovir, but HSV cannot be eradicated from the body—it is incurable.

E

AIDS

AIDS, the result of infection with the human immunodeficiency virus (HIV), is an incurable and deadly STI. AIDS attacks the body’s immune system, leaving victims unable to fight off even the mildest infections. While HIV can be transmitted by other means, sexual contact is the most common means of transmission. Women who are infected with HIV can pass the virus to their infants during pregnancy, childbirth or, less frequently, in breast milk. Treatment options for people infected with HIV include protease inhibitors, which can markedly increase survival. In spite of widespread educational and prevention programs, the CDC estimates that there are 40,000 new cases of HIV each year in the United States and that 800,000 to 900,000 Americans overall have HIV infection.

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F

Hepatitis B

One hundred times more contagious than HIV, hepatitis B passes from person to person through unprotected sexual intercourse with an infected person, or through the sharing of infected needles or other sharp instruments that break the skin. Hepatitis B can also spread during childbirth: Between 90 and 95 percent of all babies born to infected mothers get the disease during birth. The CDC estimates that 120,000 new hepatitis B infections occur each year. Hepatitis B attacks liver cells, sometimes leading to cirrhosis and cancer of the liver. In most cases hepatitis B is incurable, but arduous chemotherapy can eliminate the virus in some patients. There is a safe, effective vaccination for hepatitis B, and most states are developing or already have initiated public school immunization programs.

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