Sexually Transmitted Diseases: Overview
By Chris Woolston, M.S.
By Chris Woolston, M.S.
There are only two ways to completely protect yourself from a sexually transmitted disease. You can abstain from sex altogether or have sex only with a partner you know to be uninfected. Condoms and other barrier protection can greatly reduce the risk of most sexually transmitted diseases, but even these are not 100 percent effective.
It goes without saying that few people choose the first option -- and many others choose to forgo condoms, either occasionally or all the time. Then there are those who think they are in a monogamous relationship with an uninfected partner and are later stunned to find that they are not.
According to the Centers for Disease Control and Prevention (CDC), approximately 19 million new sexually transmitted infections occur each year, almost half of them among young people aged 15 to 24. In addition, national infection rates for syphilis and other dangerous STDs have been rising over the past few years -- a trend that worries health authorities.
More than 20 different viruses and bacteria can pass from one partner to another during sex. Many of these germs, including the bacterium that causes chlamydia and the virus that causes herpes, live on the surface of the genitals. These infections can spread during genital contact, including oral or anal sex. Some viruses -- such as HIV, the virus that causes AIDS -- live in semen and other bodily fluids. These diseases spread most easily during unprotected vaginal or anal sex.
How can I protect myself from STDs?
Unless your partner is absolutely monogamous and uninfected, you should use a latex condom or barrier for oral, anal, and vaginal sex. You can further protect yourself by limiting your number of partners. If you're considering having sex with a new partner, both of you should first be tested for STDs, according to the CDC. Many people don't even realize they have an STD, so simply asking them if they do won't necessarily help.
If you've had a risky encounter, wash your genitals with soap and water as soon as possible and consider getting tested for STDs, especially before you have sex with a new partner. Repeating these tests several months after beginning the relationship might be a good idea in some cases, too. If you're worried, talk with your doctor.
What are the common symptoms of STDs?
Keep in mind that many common infections -- chlamydia, for one -- can be very subtle or even symptom-free. Schedule a visit with your doctor if you notice any of these common symptoms of an STD:
- Unusual discharge from your genitals, such as mucus or pus
- Pain or a burning sensation during sex or urination
- Any pain in the pelvic area
- Sores on any part of the body
- Small genital blisters that turn into scabs
- A small painless ulcer (chancre) on the genitals
- Warts on or near the genitals
- A sore throat after oral sex
- In women, cramps and pain, bleeding between menstrual periods, and bleeding during or after vaginal intercourse
Other symptoms may include rectal discharge and painful or bloody bowel movements.
What are the most common types of STDs?
Different types of STDs have different consequences and different treatments. Here's a rundown of the major sexually transmitted diseases.
- Chlamydia (Chlamydia trachomatis)
Chlamydia is a bacterial infection that spreads easily during sex. According to the CDC, about 2.8 million Americans are infected with chlamydia every year, and many don't even know it. Although some infected people may notice some unusual discharge from their genitals or pain while urinating, many don't have any symptoms at all.
Chlamydia may be a quiet disease, but the consequences can be severe. If untreated, the infection can lead to pelvic inflammatory disease (PID) in women, a major cause of infertility. In men, the germ can cause epididymitis, painful swelling around a testicle that can reduce fertility. Pregnant women infected with chlamydia can pass the germ to their babies while giving birth. Babies who catch chlamydia can develop pink eye and pneumonia within the first few weeks of life.
The good news is that chlamydia is no match for modern medicine. Antibiotics can quickly clear up the infection and prevent possible complications. If you suspect that you have chlamydia, schedule an appointment with your doctor.
A simple test can detect the germ for chlamydia. Even if you don't have symptoms of chlamydia, in some cases regular testing may be a good idea. The CDC recommends annual testing for all sexually active women 25-years-old and under.
You should also be screened for chlamydia -- even if you're over 25 -- if you've had a history of STDs, have changed sex partners, had multiple partners, or had unsafe sex in the past year, according to the American College of Preventive Medicine. CDC guidelines released in 2006 also recommend that all women with chlamydia be rescreened approximately three months after their treatment is finished, because of the risk of re-infection. Note that both the person who has been diagnosed AND his or her current sex partner(s) should be treated -- since current partners are likely to carry the infection and could be reinfected if they are not treated at the same time.
- Genital herpes
Like chlamydia, genital herpes is an extremely common infection that frequently goes unnoticed. According to the CDC, at least 45 million Americans have this viral disease, but most don't know it. The symptoms are often mild or nonexistent, but some people will notice a tingling or burning sensation in the genitals followed by the appearance of painful blisters or open sores. These sores go away after a few weeks. The virus, however, will remain in the body for life.
If your symptoms are severe or if the sores keep coming back, your doctor can prescribe antiviral medications to reduce the occurrence of outbreaks. People are more infectious during outbreaks, though there is still some risk of infecting your partner even when there are no symptoms.
According to a study published in the New England Journal of Medicine, a daily dose of an antiviral drug can significantly reduce the risk of passing herpes on to a sex partner. The risk doesn't disappear, however, so anyone infected with herpes should still use condoms during sex, even if there are no visible sores.
- Human immunodeficiency virus (HIV)
HIV is the most feared of all sexually transmitted infections, and for good reason. This virus is the cause of AIDS (Acquired Immune Deficiency Syndrome), a disease that killed 2 million people worldwide in 2007 alone. In the United States, more than 500,000 have died from the disease. The disease is most often spread through sexual contact -- both heterosexual and homosexual -- and through sharing needles.
People with AIDS have extremely weak immune systems, leaving them vulnerable to opportunistic infections and certain types of cancer. If you're infected with HIV, your doctor can prescribe powerful medications to fight the virus and, hopefully, keep you from developing AIDS. Nonetheless, the path to successful AIDS treatment is not easy for most people -- the medicines must be taken every day for life in order to prevent treatment failure, and most of them have the potential to cause significant side effects.
Of course, the best way to avoid AIDS is to avoid catching HIV in the first place. The same safe-sex practices that cut the risk of other STDS -- using condoms, not sharing needles, and limiting your number of partners -- will offer powerful protection against HIV.
- Human papillomavirus (HPV)
There are 100 types of HPV, most of them harmless, and about 30 types are sexually transmitted. Some types of HPV can lead to genital warts and others can lead to cancer. At least 50 percent of all adults will contract this sexually transmitted virus at some point in their lives. According to the CDC, 20 million Americans have HPV today and about 6.2 million new infections occur every year.
The immune system usually fends off the germ before it has a chance to do any damage. Sometimes, however, the virus can linger for years in women and eventually cause cancer of the cervix if undetected or untreated. Pap smears are the best way to prevent this most feared complication of HPV. In 2003, the Food and Drug Administration approved a new HPV test for women over 30, but it is only used to screen for cervical cancer. Since only a tiny percentage of women who have the virus will ever develop cervical cancer, the test has the potential to cause a lot of unnecessary worry. If you're a sexually active woman over 30, ask your doctor if you should have an HPV test along with your regular Pap smear.
The most recognizable symptom of an HPV infection is genital warts. If you have them, make a doctor's appointment immediately and avoid sex until you and your partner are treated.
Since the virus is spread through skin-to-skin contact, the only way to prevent it is to avoid exposure. However, a new vaccine protects women from the most common HPV strains that cause genital warts and cervical cancer. The CDC recommends the vaccine for girls ages 11 and 12, and for girls and women between the ages of 13 through 26 who have not yet been vaccinated, or who haven't completed the vaccine series. Although evidence doesn't show that latex condoms prevent the spread of HPV, it does suggest that condoms may help reduce the risk of contracting genital warts or cervical cancer, according to the CDC.
This bacterial disease has been going around for centuries, and despite advances in medical treatments, it shows no signs of going away. The CDC receives roughly 350,000 reports of new gonorrhea cases each year, and another 350,000 infections probably go unreported. The main symptoms of the disease are discharge from the genitals and difficult or painful urination. If untreated, gonorrhea can lead to infection of the reproductive tract and even spread to the joints and blood; in women, it can cause pelvic inflammatory disease (PID) and infertility, as well as serious infections and blindness in newborns. Prompt treatment with antibiotics can clear up the infection and prevent complications.
Symptoms of gonorrhea include pain or burning when urinating, yellow or bloody vaginal discharge, rectal itching or discharge, painful or bloody bowel movements, and pus or pain in the penis. Using latex condoms each time you have vaginal or rectal sex will help prevent the disease.
The rates of syphilis declined by 89.2 percent from 1990 to 2000, although the number of cases rose from 5,979 in 2000 to 11,466 in 2007. Since syphilis increases the risk of acquiring and spreading HIV, the virus that causes AIDS, this increase worries many researchers.
If untreated, syphilis can cause heart and nervous system disorders, including blindness, and death. The first symptom of the disease is often a painless ulcer called a chancre, often found on the genitals. Several weeks later, a rash may appear over the whole body, generally on the palms and the soles of the feet. The rash will look like "brown sores about the size of a penny," according to the NIH. Other symptoms include fatigue, a mild fever, hair loss, and swollen lymph glands.
In May 2006, the CDC released an updated National Plan to Eliminate Syphilis. If you think you have been exposed to the disease, or have symptoms, get tested immediately.
- Hepatitis B
Hepatitis B is caused by a virus that assaults the liver. The virus can cause lifelong infection as well as liver scarring, liver cancer or liver failure, and even death. Symptoms of hepatitis B infection include fatigue, jaundice, abdominal pain, loss of appetite, nausea and vomiting, and joint pain. However, 30 percent of those affected show no symptoms at all.
A hepatitis B vaccine is your best protection against this serious disease. Additional precautions include using latex condoms and never sharing needles, drugs, or personal items, such as razors or toothbrushes.
What if I don't have insurance or money to get tested?
Call your local health department about public clinics where you can get tested for STDs at no charge. If the clinic is crowded, you may have to wait two or more hours to see the doctor, so bring a magazine and plan for a fairly long wait. It's well worth it.
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