Skipper Chong Warson

re you completely certain that you don't have a sexually transmitted disease? For most men and women, the answer is a confident "yes" -- they are sexually inactive, monogamous, practice safe sex, and/or get checked regularly by their doctor. But others, who may assume they're clear because they don't show any obvious STD symptoms, may be raising their risk of cancer and AIDS, flirting with liver disease, or threatening their fertility.

Thankfully, many sexually transmitted diseases can now be treated and cured when they're diagnosed. However, knowing that you've been infected is sometimes harder than you might imagine.

Chlamydia

Chlamydia, the most common STD in the United States, is caused by a bacterium that can be spread through vaginal, anal, or oral sex. Though symptoms can include stomach pain, fever, testicular pain, urethral or vaginal discharge, itching, redness, and painful urination, chlamydial infection often shows no symptoms. According to the Centers for Disease Control and Prevention (CDC), in Atlanta, approximately 75 percent of women and 50 percent of men show no symptoms when infected.

Of course, the best way to deal with any STD is to prevent catching it in the first place. "Condoms provide excellent protection for most common STDs. While not universally preventive, they are the best precaution available -- upwards of 95 percent or higher," says Dr. Celentano.

"Chlamydia is probably, for women, the most commonly undetected STD," says David D. Celentano, Sc.D., an expert in STDs at Johns Hopkins University. "Chlamydia has been associated with ectopic pregnancy (a painful and potentially deadly condition in which the fertilized egg cannot descend through the fallopian tube, usually requiring surgical removal of the pregnancy), and more rarely, with pelvic inflammatory disease, which is associated with infertility," he says. Chlamydia can also be passed from infected mothers to their babies during childbirth. Luckily, chlamydia is treatable with antibiotics.

Gonorrhea

Gonorrhea, the most commonly reported STD in the United States, is also caused by a bacterium and can infect the genitals, throat, and anus. At highest risk are sexually active men and women between 20 and 24 years old.

Like chlamydia, gonorrhea can lurk silently in the body, especially in women. When symptoms are present, they often include a yellow-green vaginal or urethral discharge, fever, painful and frequent urination, testicular pain, and genital irritation. Untreated, gonorrhea can spread through the body and cause sterility in men and PID and infertility in women.

"The good news is that when it is detected, it responds almost completely to single-dose [antibiotic] therapy," says Dr. Celentano. Because gonorrhea and chlamydia often travel together, doctors often treat gonorrhea patients for possible chlamydia infection, just to be safe.

Genital warts

The commonplace human papilloma virus (HPV), the virus that causes genital warts, infects 24 million Americans a year, making it the most common viral STD in the United States. While most HPV infections are not a serious threat, some strains can increase the risk of cervical cancer in women -- and most of these strains do not cause visible genital warts. The Pap smear is the standard method for diagnosing cancerous cells of the cervix. Fortunately, women who get regular Pap smears will virtually eliminate their risk of cervical cancer.

HIV

Twenty years after it was first reported in the United States, there is still no cure for the human immunodeficiency virus (HIV), which causes the fatal disease AIDS. Unfortunately, many people do not develop any symptoms upon infection with HIV. Some people, however, develop a flu-like illness within a month or two after exposure to the virus. They may develop fever, headache, malaise, and enlarged lymph nodes, which usually disappear within a week to a month and are often mistaken for symptoms of another viral infection. The danger of remaining sexually active while infected with HIV is obvious, and anyone who suspects that they may be infected needs to be tested.

Hepatitis B

Hepatitis B is usually caused by a viral infection in the liver. Estimated to be 100 times more contagious than AIDS, hepatitis B can cause cirrhosis and scarring of the liver. It also increases the risk of liver cancer 200-fold. Many hepatitis B carriers, however, show no symptoms. Others may show signs of jaundice, nausea, vomiting, fever, or loss of appetite. Like chlamydia, hepatitis B can be passed from mother to child. There is no cure for this disease, but there are drugs available to reduce liver irritation and swelling.

Less of a worry

Some hidden STDs do not have such serious consequences. Certain people infected with genital herpes, a relatively harmless but permanent viral infection, show no symptoms at all. Signs of herpes infection usually develop within 2 to 20 days after contact with the virus. But a first attack with the virus can be so mild that it goes unnoticed.

Also in the category of relatively harmless is trichomoniasis, or "trich," infection. It is usually transmitted through sexual contact but can also be transmitted by wet clothes or towels. Men usually have no symptoms and, if left untreated, trichomoniasis infection can produce urethral and bladder infections in both men and women.

A less prevalent STD, syphilis, does not show up right away either. Once among the most dangerous of STDs, syphilis can be easily treated with antibiotics if caught before permanent damage occurs. It does, however, up the chances for contracting HIV, so anyone diagnosed with syphilis should be tested for HIV.

STD prevention

If you are not sure that you're safe, you should cast shyness to the wind and ask your doctor for the appropriate STD tests. It's the only way to know for certain that you don't have any hidden STDs. Jorma Paavonen, M.D., of the University of Helsinki, in Finland, recommends a few specific tests for sexually active individuals. "Sexually active people should get tested for chlamydia and gonorrhea, and they should also have a baseline HIV antibody test. Women should additionally undergo a vaginal wet mount (used to determine different causes of vaginal irritation and discharge) and a Pap smear," says Dr. Paavonen.

Of course, it's best to avoid catching an STD in the first place. "Condoms provide excellent protection for most common STDs. While not universally preventive (for example, they do not provide full protection from herpes or HPV), they are the best precaution available -- upwards of 95 percent or higher," says Dr. Celentano.

Women also have the option of using a female condom. "The female condom appears to provide about the same protection as the male latex condom when used properly," says Dr. Celentano. "Topical vaginal microbicides are also a novel option that may provide additional protection against STDs," says Dr. Paavonen.

The unfortunate and ironic thing about STDs is that the least painful ones can be the most threatening in the long run. To ensure long-term good health, taking a trip to the doctor's office for a few tests seems like a small price to pay - doesn't it?

Related link:

• Outside link: American Social Health Association

Additional Information:

• The CDC National STD Hotline: 800-227-8922

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