Overview

Sexually transmitted diseases (STDs) are passed from one person to another through sex. About one in five people in the United States have an STD with 25 percent of new cases occurring in teens. STDs are some of the most common infections.

STDs affect men and women of all backgrounds. Risks increase when people have multiple sex partners throughout their lives. Many STDs don't have symptoms. This is particularly true for women, making STDs a silent epidemic. These diseases can be spread through anal, vaginal and oral sex.

Some STDs may cause infertility, cancer or even death if not treated early. Get treatment as soon as possible and get regular exams from your doctor if you think you are at high risk. STDs in pregnant women may cause spontaneous abortion, low birth weight, premature birth, brain damage in the baby or infection of the infant with the disease.

To prevent STDs:

• Use a latex condom every time you engage in sexual activity. Animal skin or novelty condoms don't protect you.
• Abstain from sex.
• Have only one trusted sex partner who is also monogamous.
• Prior to having sexual relations, ask your partner about any history of STDs.
• A new vaccine, Gardasil, is available that can prevent genital warts if given to girls before they become sexually active.

Herpes

Herpes generally come in two forms: HSV-type 1 and HSV-type 2. Herpes in the mouth most often is due to HSV-type 1 and usually causes cold sores, but can cause genital and perianal infections as well. Type 1 infects the mouth and face and is spread through such activity as kissing. Most often, type 2 is usually transmitted by sexual contact. Often, people who have herpes don't have symptoms, but others have outbreaks of blisters or ulcers. Even without symptoms, the disease can still be spread. Herpes does not have a cure, but outbreaks can be suppressed with medication. The disease is most contagious when the sores are open and least contagious when skin is normal. Outbreaks last about two weeks and can reappear at any time. As the years pass after initial infection, outbreaks may become less frequent, usually ending almost entirely within five or six years.

A mother can transmit the disease to the child during delivery. About 30 percent to 60 percent of infected babies die within the first month. The babies who live may develop mental retardation and seizures.

Chlamydia

Chlamydia is the most common bacterial sexually transmitted disease in the United States and is very common among young adults and teenagers. Usually there are no early symptoms, so people aren't aware they have the disease. About 75 percent of women and half of men who have the disease don't know it.

Chlamydia is a leading cause of pelvic inflammatory disease that can cause infertility or ectopic pregnancy. Chlamydia infection can leave adhesions (scar tissue) in the female genital tract, which may block the fertilized embryo from entering or traveling down the fallopian tube. Attachment of the developing fetus inside the fallopian tubes results in an ectopic pregnancy, a dangerous condition that requires emergency surgery. The disease can also increase the risk of getting or spreading HIV. However, Chlamydia can be cured with antibiotics. Chlamydia occurs four times more often than gonorrhea, another bacterial STD. A pregnant woman may pass the disease to her baby during delivery, causing infection of the eyes or possibly pneumonia. Without treatment, the baby may have permanent vision loss. Chlamydia can also cause early labor and delivery.

HPV and genital warts

The human papilloma virus (HPV) is a group of over 100 types of viruses that can cause warts. Usually, genital HPVs are transmitted through sex. According to the Centers of Disease Control and Prevention (CDC), more than 25 percent of women in the U.S. are infected with HPV, which is, thought to be the cause of most cases of cervical cancer as well as many cases of vulval and vaginal cancer. The CDC recommends that Gardisil, a vaccine that can prevent HPV infection, be given routinely to girls at age 11 to 12.

Depending on the type of HPV, warts can be found on feet, hands or other parts of the body, with some in the genital area. Not everyone has symptoms. About half of all people with HPV never develop genital warts. However, they can still spread the disease. Women should have regular Pap smears so that pre-cancerous conditions can be treated. Genital warts are very contagious. About two thirds of those who have sexual contact with someone with genital warts develop them within three months.

Syphilis

Once deadly, syphilis now can be treated easily and effectively if diagnosed early. The disease is spread through vaginal, anal or oral sex. In primary syphilis (the first stage of infection), the bacteria is spread through contact with genital ulcers. Because the sores are painless, many people do not know they have syphilis and do not get help. If left untreated, the disease silently progresses to the organs and nervous system. Syphilis can cause heart disease, dementia, blindness, paralysis and death. Syphilis increases the risk of transmitting or getting HIV. An unrecognized syphilis infection during pregnancy may cause blindness, severe organ damage and even death to the infant.

Gonorrhea

This is a bacterial infection of the penis, vagina or anus. Someone with the disease may have pain or a burning feeling and a pus-like discharge. However, many people do not know they have the disease because they do not have any symptoms. Gonorrhea grows and multiplies quickly in moist, warm areas of the body, including the reproductive tract, the mouth and the rectum. In most women, gonorrhea is confined to the cervix (cervicitis). However, in one in five women, infection spreads to the upper genital tract (uterus and fallopian tubes) which can result in pelvic inflammatory disease, infertility or ectopic pregnancy and eventually infertility. The disease is transmitted through the anus or vagina or through oral sex. Left untreated, gonorrhea increases the risk of contracting HIV. Gonorrhea can enter the bloodstream, leading to an infection throughout the body, often causing pain and swelling in the joints. In pregnancy, the disease can be spread to the child during delivery, possibly causing permanent eye damage.

HIV/AIDS

Human immunodeficiency virus (HIV) is the virus that causes acquired immune deficiency syndrome (AIDS). If left untreated, HIV destroys the immune system, resulting in deadly opportunistic infections. Before therapy was developed to treat HIV/AIDS, the average life expectancy after diagnosis was only one to two years. Common bacteria, viruses and other microbes are harmless to healthy people with an intact immune system. However, those same organisms are "opportunistic" when they produce severe pneumonia and other serious illness in an immunocompromised host with AIDS who cannot mount an immune response.

AIDS is the final stage of HIV. HIV is spread by sexual contact, by intravenous drug users who share needles and other blood-exposed products, and from mother to baby during delivery. About 20 percent of newborns of untreated mothers in the United States acquire HIV. The virus can enter the body through the lining of the vagina, vulva, penis, rectum or mouth during sex. HIV is also spread through contact with infected blood.

Pelvic inflammatory disease (PID)

PID is an infection of a woman's reproductive organs, involving the uterus, fallopian tubes, ovaries and surrounding pelvic tissues. These organs become inflamed, irritated and swollen when infected with Chlamydia and gonorrhea, the most common types of PID infection. Women with repeated episodes often have problems getting pregnant. Adhesions or scars left after PID infections block the fallopian tubes. A woman cannot get pregnant naturally if her egg cell cannot enter or travel down the blocked fallopian tube, where fertilization by sperm takes place. She may also develop an ectopic pregnancy (pregnancy occurring outside the uterus, such as in the fallopian tubes) when the fertilized egg cell continues to grow in the scarred fallopian tube because it cannot enter the uterus.

Infertility occurs in about 20 percent of women with PID. Most women with tubal infertility, however, never have symptoms. PID can also cause chronic pelvic pain because of the scar tissue and changes of the pelvic organs. Surgery may be required for this condition.

Trichomoniasis

Trichomoniasis, or trich, usually causes a discharge and a fishy odor from the vagina. In men, it is usually unrecognized, although rarely it can cause urinary infection. The organism is transmitted through vaginal sex. Although the disease doesn't cause serious health problems, trichomoniasis can increase the chances of getting HIV. The heavy discharge caused by trichomoniasis can irritate your skin. The disease may also cause babies to be born too early or with low birth weights.

Hepatitis

Hepatitis is an inflammation of the liver that can be caused by viruses, certain medications and alcohol abuse. Five viral forms are A, B, C, D and E. Hepatitis B can be easily spread through sexual contact, though cases of A, C and D occur less commonly.

Hepatitis B. Hepatitis B (HBV) causes acute and chronic liver disease. It is found in highest concentration in blood. The disease is detected in low levels in semen, vaginal fluids and saliva. HBV can be transmitted from mother to baby during delivery. Most adults fight off the infection of the virus, but HBV becomes a long-term problem in 10 percent of cases. Severe cases can cause permanent liver damage, liver failure, liver cancer and death. Chronic HBV can be controlled, but and may be curable with medication. According to the American Social Health Association, HBV is 100 times more contagious than HIV.

Pubic lice

The cause of "crabs," pubic lice are pale, gray insects that look like tiny crabs. They are spread almost exclusively by sexual contact, and not by sharing a toilet seat. Eggs are usually attached to the base of pubic hairs, underarm hair, eyelashes and eyebrows.

Prognosis

Despite how common STDs are, the subject remains taboo for some. People with STDs may feel ashamed, embarrassed or depressed. If you think you may have an STD, talk to your health care provider. Some diseases may be cured or at least controlled. If untreated, some can cause serious damage, such as infertility.

Taking preventive measures - abstinence, monogamy and using latex condoms - remain the best strategies for avoiding STDs.

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