What are sexually transmitted diseases STDs

Sexually transmitted diseases (STDs) are infections that can be transferred from one person to another through any type of sexual contact. STDs are sometimes referred to as sexually transmitted infections (STIs) since they involve the transmission of a disease-causing organism from one person to another during sexual activity. It is important to realize that sexual contact includes more than just sexual intercourse (vaginal and anal). Sexual contact includes kissing, oral-genital contact, and the use of sexual "toys," such as vibrators. STDs probably have been around for thousands of years, but the most dangerous of these conditions, the acquired immunodeficiency syndrome (AIDS), has only been recognized since 1984.

Many STDs are treatable, but effective cures are lacking for others, such as HIV, HPV, and hepatitis B and C. Even gonorrhea, once easily cured, has become resistant to many of the older traditional antibiotics. Many STDs can be present in, and spread by, people who do not have any symptoms of the condition and have not yet been diagnosed with an STD. Therefore, public awareness and education about these infections and the methods of preventing them is important.

There really is no such thing as "safe" sex. The only truly effective way to prevent STDs is abstinence. Sex in the context of a monogamous relationship wherein neither party is infected with a STD also is considered "safe." Most people think that kissing is a safe activity. Unfortunately, syphilis, herpes, and other infections can be contracted through this relatively simple and apparently harmless act. All other forms of sexual contact carry some risk. Condoms are commonly thought to protect against STDs. Condoms are useful in decreasing the spread of certain infections, such as chlamydia and gonorrhea; however, they do not fully protect against other infections such as genital herpes, genital warts, syphilis, and AIDS. Prevention of the spread of STDs is dependent upon the counseling of at-risk individuals and the early diagnosis and treatment of infections.

Gonorrhea is a bacterial infection caused by the organism Neisseria gonorrheae that is transmitted by sexual contact. Gonorrhea is one of the oldest known sexually transmitted diseases. It is estimated that over one million women are currently infected with gonorrhea. Among women who are infected, 25%-40% also will be infected with chlamydia, another type of bacteria that causes another STD. (Chlamydia infection is discussed later in this article.)

Contrary to popular belief, gonorrhea cannot be transmitted from toilet seats or door handles. The bacterium that causes gonorrhea requires very specific conditions for growth and reproduction. It cannot live outside the body for more than a few seconds or minutes, nor can it live on the skin of the hands, arms, or legs. It survives only on moist surfaces within the body and is found most commonly in the vagina, and, more commonly, the cervix. (The cervix is the end of the uterus that protrudes into the vagina.) It can also live in the tube (urethra) through which urine drains from the bladder. Gonorrhea can even exist in the back of the throat (from oral-genital contact) and in the rectum.

Over 50% of infected women have no symptoms, especially in the early stages of the infection. Symptoms of gonorrhea include burning or frequent urination, a yellowish vaginal discharge, redness and swelling of the genitals, and a burning or itching of the vaginal area. If untreated, gonorrhea can lead to a severe pelvic infection with inflammation of the Fallopian tubes and ovaries. Gonorrheal infection of the Fallopian tubes can lead to a serious, painful infection of the pelvis known as pelvic inflammatory disease or PID. PID occurs in 10%-40% of women with gonorrheal infection of the uterine cervix. Symptoms of pelvic infection include fever, pelvic cramping, abdominal pain, or pain with intercourse. Pelvic infection can lead to difficulty in becoming pregnant or even sterility. Occasionally, if the infection is severe enough, a localized area of infection and pus (an abscess) forms, and major surgery may be necessary and even lifesaving. Gonorrhea infection in people with conditions causing serious abnormal immune function, such as AIDS, can also be more serious.

Testing for gonorrhea is done by swabbing the infected site (rectum, throat, cervix) and identifying the bacteria in the laboratory either through culturing of the material from the swab (growing the bacteria) or identification of the genetic material from the bacteria. Sometimes the tests do not show bacteria because of sampling errors (the sampled area does not contain bacteria) or other technical difficulties, even when the woman has an infection. Newer tests to diagnose gonorrhea involve the use of DNA probes or amplification techniques (for example, polymerase chain reaction, or PCR) to identify the genetic material of the bacteria. These tests are more expensive than cultures but typically yield more rapid results.

In the past, the treatment of uncomplicated gonorrhea was fairly simple. A single injection of penicillin cured almost every infected person. Unfortunately, there are new strains of gonorrhea that have become resistant to various antibiotics, including penicillins, and are therefore more difficult to treat. Fortunately, gonorrhea can still be treated by other injectable or oral medications.

Uncomplicated gonococcal infections of the cervix, urethra, and rectum, are usually treated by a single injection of ceftriaxone intramuscularly or by 400mg of cefixime (Suprax) in a single oral dose. For uncomplicated gonococcal infections of the pharynx, the recommended treatment is 125 mg of ceftriaxone in a single IM dose.

Alternative regimens for uncomplicated gonococcal infections of the cervix, urethra, and rectum are 2 g of spectinomycin in nonpregnant women (not available in the United States) in a single IM dose or single doses of cephalosporins (ceftizoxime, 500 mg IM; or cefoxitin, 2 g IM, administered with probenecid (Benemid), 1 g orally; or cefotaxime, 500 mg IM).

Treatment should always include medication that will treat chlamydia [for example, azithromycin (Zithromax, Zmax) or doxycycline (Vibramycin, Oracea, Adoxa, Atridox and others)] as well as gonorrhea, because gonorrhea and chlamydia frequently exist together in the same person. The sexual partners of women who have had either gonorrhea or chlamydia must receive treatment for both infections since their partners may be infected as well. Treating the partners also prevents reinfection of the woman. Women suffering from PID require more aggressive treatment that is effective against the bacteria that cause gonorrhea as well as against other organisms. These women often require intravenous administration of antibiotics.

It is important to note that doxycycline, one of the recommended drugs for treatment of PID, is not recommended for use in pregnant women.

Gonorrhea is one of the easier STDs to prevent because the bacterium that causes the infection can survive only under certain conditions. The use of condoms protects against gonorrhea infection. Since the organism can live in the throat, condoms should be used during oral-genital contact as well.

Chlamydia (Chlamydia trachomatis) is a bacterium that causes an infection that is very similar to gonorrhea in the way that it is spread and the symptoms it produces. It is common and affects approximately 4 million women annually. Like gonorrhea, the chlamydia bacterium is found in the cervix and urethra and can live in the throat or rectum. Both infected men and infected women frequently lack symptoms of chlamydia infection. Thus, these individuals can unknowingly spread the infection to others. Another strain (type) of Chlamydia trachomatis, which can be distinguished in specialized laboratories, causes the STD known as lymphogranuloma venereum (LGV; see below).

The majority of women with chlamydia do not have symptoms. Cervicitis (infection of the uterine cervix) is the most common manifestation of the infection. While about half of women with chlamydial cervicitis have no symptoms, others may experience vaginal discharge or abdominal pain. Infection of the urethra is often associated with chlamydial infection of the cervix. Women with infection of the urethra (urethritis) have the typical symptoms of a urinary tract infection, including pain upon urination and the frequent and urgent need to urinate.

Chlamydia is very destructive to the Fallopian tubes. It can also cause severe pelvic infection. If untreated, about 30% of women with chlamydia will develop pelvic inflammatory disease (PID; see above). Because it is common for infected women to have no symptoms, chlamydial infection is often untreated and results in extensive destruction of the Fallopian tubes, fertility problems and tubal pregnancy.

Chlamydial infection, like gonorrhea, is associated with an increased incidence of premature births. In addition, the infant can acquire the infection during passage through the infected birth canal, leading to serious eye damage or pneumonia. For this reason, all newborns are treated with eye drops containing an antibiotic that kills chlamydia. Treatment of all newborns is routine because of the large number of infected women without symptoms and the dire consequences of chlamydial eye infection to the newborn.

Chlamydia can be detected on material collected by swabbing the cervix during a traditional examination using a speculum, but noninvasive screening tests done on urine or on self-collected vaginal swabs are less expensive and sometimes more acceptable to patients. While culturing of the organism can confirm the diagnosis, this method is limited to research laboratories and forensic investigations. For routine diagnostic use, newer and inexpensive diagnostic tests that depend upon identification and amplification of the genetic material of the organism have replaced the older, time-consuming culture methods.

Treatment of chlamydia involves antibiotics. A convenient single-dose therapy for chlamydia is 1 gm of azithromycin (Zithromax, Zmax) by mouth. Alternative treatments are often used, however, because of the high cost of this medication. The most common alternative treatment is a 100 mg oral dose of doxycycline (Vibramycin, Oracea, Adoxa, Atridox and others) twice per day for seven days. Unlike gonorrhea, there has been little, if any, resistance of chlamydia to currently used antibiotics. There are many other antibiotics that also have been effective against chlamydia. As with gonorrhea, a condom or other protective barrier prevents the spread of the infection.

Syphilis is an STD that has been around for centuries. It is caused by a microscopic bacterial organism called a spirochete. The scientific name for the organism is Treponema pallidum. The spirochete is a wormlike, spiral-shaped organism that wiggles vigorously when viewed under a microscope. It infects the person by burrowing into the moist, mucous-covered lining of the mouth or genitals. The spirochete produces a classic, painless ulcer known as a chancre.

There are three stages of syphilis, along with an inactive (latent) stage. Formation of an ulcer (chancre) is the first stage. The chancre develops any time from 10 to 90 days after infection, with an average time of 21 days following infection until the first symptoms develop. Syphilis is highly contagious when the ulcer is present.

The infection can be transmitted from contact with the ulcer which teems with spirochetes. If the ulcer is outside of the vagina or on the male’s scrotum, condoms may not prevent transmission of the infection by contact. Similarly, if the ulcer is in the mouth, merely kissing the infected individual can spread the infection. The ulcer can resolve without treatment after three to six weeks, but the disease can recur months later as secondary syphilis if the primary stage is not treated.

In most women, an early infection resolves on its own, even without treatment. However, 25% will proceed to the second stage of the infection called "secondary" syphilis, which develops weeks to months after the primary stage and lasts from four to six weeks. Secondary syphilis is a systemic stage of the disease, meaning that it can involve various organ systems of the body. In this stage, patients can initially experience many different symptoms, but most commonly they develop a skin rash, typically appearing on the palms of the hands or the bottoms of the feet, that does not itch. Sometimes the skin rash of secondary syphilis is very faint and hard to recognize; it may not even be noticed in all cases. This secondary stage can also include hair loss, sore throat, white patches in the nose, mouth, and vagina, fever, and headaches. There can be lesions on the genitals that look like genital warts but are caused by spirochetes rather than the wart virus. These wartlike lesions, as well as the skin rash, are highly contagious. The rash can occur on the palms of the hands, and the infection can be transmitted by casual contact.

Subsequent to secondary syphilis, some patients will continue to carry the infection in their body without symptoms. This is the so-called latent stage of the infection. Then, with or without a latent stage, which can last as long as 20 or more years, the third (tertiary) stage of the disease can develop. At this stage, syphilis usually is no longer contagious. Tertiary syphilis is also a systemic stage of the disease and can cause a variety of problems throughout the body including:

√ abnormal bulging of the large vessel leaving the heart (the aorta), resulting in heart problems;
√ the development of large nodules (gummas) in various organs of the body;
√ infection of the brain, causing a stroke, mental confusion, meningitis (type of brain infection), problems with sensation, or weakness (neurosyphilis);
√ involvement of the eyes leading to sight deterioration;
√ involvement of the ears resulting in deafness. The damage sustained by the body during the tertiary stage of syphilis is severe and can even be fatal.

Syphilis can be diagnosed by scraping the base of the ulcer and looking under a special type of microscope (dark field microscope) for the spirochetes. However, since these microscopes are rarely detected, the diagnosis is most often made and treatment is prescribed based upon the appearance of the chancre. Diagnosis of syphilis is complicated by the fact that the causative organism cannot be grown in the laboratory. Therefore, cultures of affected areas cannot be used for diagnosis.

Special blood tests can also be used to diagnose syphilis. The standard screening blood tests for syphilis are called the Venereal Disease Research Laboratory (VDRL) and Rapid Plasminogen Reagent (RPR) tests. These tests detect the body’s response to the infection, but not to the actual Treponema organism that causes the infection. These tests are thus referred to as non-treponemal tests. Although the non-treponemal tests are very effective in detecting evidence of infection, they can also produce a positive result when no infection is actually present (so-called false-positive results for syphilis). Consequently, any positive non-treponemal test must be confirmed by a treponemal test specific for the organism causing syphilis, such as the microhemagglutination assay for T. pallidum (MHA-TP) and the fluorescent treponemal antibody absorbed test (FTA-ABS). These treponemal tests directly detect the body’s response to Treponema pallidum.

Depending on the stage of disease and the clinical manifestations, the treatment options for syphilis vary. Long-acting penicillin injections have been very effective in treating both early and late stage syphilis. The treatment of neurosyphilis requires the intravenous administration of penicillin. Alternative treatments include oral doxycycline or tetracycline.

Women who are infected during pregnancy can pass on the infection to the fetus through the placenta. Penicillin must be used in pregnant patients with syphilis since other antibiotics do not effectively cross the placenta to treat the infected fetus. Left untreated, syphilis can lead to blindness or even death of the infant.

Genital herpes, also commonly called "herpes," is a viral infection by the herpes simplex virus (HSV) that is transmitted through intimate contact with the mucous-covered linings of the mouth or the vagina or the genital skin. The virus enters the linings or skin through microscopic tears. Once inside, the virus travels to the nerve roots near the spinal cord and settles there permanently.

When an infected person has a herpes outbreak, the virus travels down the nerve fibers to the site of the original infection. When it reaches the skin, the typical redness and blisters occur. After the initial outbreak, subsequent outbreaks tend to be sporadic. They may occur weekly or even years apart.

Two types of herpes viruses are associated with genital lesions: herpes simplex virus-1 (HSV-1) and herpes simplex virus-2 (HSV-2). HSV-1 more often causes blisters of the mouth area while HSV-2 more often causes genital sores or lesions in the area around the anus. The outbreak of herpes is closely related to the functioning of the immune system. Women who have suppressed immune systems, because of stress, infection, or medications, have more frequent and longer-lasting outbreaks.

It is estimated that as many as 50 million persons in the United States are infected with genital HSV. Genital herpes is spread only by direct person-to-person contact. It is believed that 60% of sexually active adults carry the herpes virus. Part of the reason for the continued high infection rate is that most women infected with the herpes virus do not know that they are infected because they have few or no symptoms. In many women, there are "atypical" outbreaks where the only symptom may be mild itching or minimal discomfort. Moreover, the longer the woman has had the virus, the fewer the symptoms they have with their outbreaks. Finally, the virus can shed from the cervix into the vagina in women who are not experiencing any symptoms.

Once exposed to the virus, there is an incubation period that generally lasts 3 to 7 days before a lesion develops. During this time, there are no symptoms and the virus cannot be transmitted to others. An outbreak usually begins within two weeks of initial infection and manifests as an itching or tingling sensation followed by redness of the skin. Finally, a blister forms. The blisters and subsequent ulcers that form when the blisters break, are usually very painful to touch and may last from 7 days to 2 weeks. The infection is definitely contagious from the time of itching to the time of complete healing of the ulcer, usually within 2-4 weeks. However, as noted above, infected individuals can also transmit the virus to their sex partners in the absence of a recognized outbreak.

Genital herpes is suspected when multiple painful blisters occur in a sexually exposed area. During the initial outbreak, fluid from the blisters may be sent to the laboratory to try and culture the virus, but cultures only return a positive result in about 50% of those infected In other words, a negative test result from a blister is not as helpful as a positive test result, because the test may be a false-negative test. However, if a sample of a fluid-filled blister (in the early stage before it dries up and crusts) tests positive for herpes, the test result is very reliable. Cultures taken during an initial outbreak of the condition are more likely to be positive for the presence of HSV than cultures from subsequent outbreaks.

There are also blood tests that can detect antibodies to the herpes viruses that can be useful in some situations. These tests are specific for HSV-1 or HSV-2 and are able to demonstrate that a person has been infected at some point in time with the virus, and they may be useful in identifying infection that does not produce characteristic symptoms. However, because false-positive results can occur and because the test results are not always clear-cut, they are not recommended for routine use in screening low-risk populations for HSV infection.

Other diagnostic tests such as polymerase chain reaction (PCR) to identify the genetic material of the virus and rapid fluorescent antibody screening tests are used to identify HSV in some laboratories.

Although there is no known cure for herpes, there are treatments for the outbreaks. There are oral medications, such as acyclovir (Zovirax), famciclovir (Famvir), or valacyclovir (Valtrex) that prevent the virus from multiplying and even shorten the length of the eruption. Although topical (applied directly on the lesions) agents exist, they are generally less effective than other medications and are not routinely used. Medication that is taken by mouth, or in severe cases intravenously, is more effective. It is important to remember that there is still no cure for genital herpes and that these treatments only reduce the severity and duration of outbreaks.

Since the initial infection with HSV tends to be the most severe episode, an antiviral medication usually is warranted. These medications can significantly reduce pain and decrease the length of time until the sores heal, but treatment of the first infection does not appear to reduce the frequency of recurrent episodes.

In contrast to a new outbreak of genital herpes, recurrent herpes episodes tend to be mild, and the benefit of antiviral medications is only derived if therapy is started immediately prior to the outbreak or within the first 24 hours of the outbreak. Thus, the antiviral drug must be provided for the patient in advance. The patient is instructed to begin treatment as soon as the familiar pre-outbreak "tingling" sensation occurs or at the very onset of blister formation.

Finally, suppressive therapy to prevent frequent recurrences may be indicated for those with more than six outbreaks in a given year. Acyclovir (Zovirax), famciclovir Famvir), and valacyclovir (Valtrex) may all be given as suppressive therapies.

Herpes can be spread from one part of the body to another during an outbreak.

√ Therefore, it is important not to touch the eyes or mouth after touching the blisters or ulcers.
√ Thorough hand washing is a must during outbreaks.
√ Clothing that comes in contact with ulcers should not be shared with others.
√ Couples that want to minimize the risk of transmission should always use condoms if a partner is infected. Unfortunately, even when an infected partner isn;t currently having an outbreak, herpes can be spread.
√ Couples may also want to consider avoiding all sexual contact, including kissing, during an outbreak of herpes.
√ Since an active genital herpes outbreak (with blisters) during labor and delivery can be harmful to the infant, pregnant women who suspect that they have genital herpes should tell their doctor. Women who have herpes and are pregnant can have a vaginal delivery as long as they are not experiencing symptoms or actually having an outbreak while in labor.

More than 40 types of HPV, which are the cause of genital warts (also known as condylomata acuminata or venereal warts), can infect the genital tract of men and women. These warts are primarily transmitted during sexual contact. Other, different HPV types generally cause common warts elsewhere on the body. HPV infection has long been known to be a cause of cervical cancer and other anogenital cancers in women, and it has also been linked with both anal and penile cancer in men.

HPV infection is now considered to be the most common sexually transmitted infection in the US, and it is believed that at least 75% of the reproductive-age population has been infected with sexually transmitted HPV at some point in life.

HPV infection is common and does not usually lead to the development of warts, cancers, or specific symptoms. In fact, the majority of people infected with HPV have no symptoms or lesions at all. The ultimate test to detect HPV involves identification of the genetic material (DNA) of the virus.

Of note, it has not been definitively established whether the immune system is able to permanently clear the body of an HPV infection. For this reason, it is impossible to predict exactly how common HPV infection is in the general population.

Asymptomatic (those without HPV-induced warts or lesions) people who have HPV infections are still able to spread the infections to others through sexual contact.

A typical appearance of a genital lesion may prompt the physician to treat without further testing, especially in someone who has had prior outbreaks of genital warts. Genital warts usually appear as small, fleshy, raised bumps, but they can sometimes be extensive and have a cauliflower-like appearance. They may occur on any sexually-exposed area. In many cases genital warts do not cause any symptoms, but they are sometimes associated with itching, burning, or tenderness.

HPV can sometimes be suspected by changes that appear on a Pap smear, although Pap smears were not really designed to detect HPV. In the case of an abnormal Pap smear, the clinician will often do advanced testing on the material to determine if, and which kind, of HPV may be present. HPV can also be detected if a biopsy (for example, from a genital wart or from the uterine cervix) is sent to the laboratory for analysis.

There is no cure or treatment that can eradicate HPV infection, so the only treatment is to remove the lesions caused by the virus. Unfortunately, even removal of the warts does not necessarily prevent the spread of the virus, and genital warts frequently recur. None of the available treatments are ideal or clearly superior to others.

A treatment that can be administered by the patient is a 0.5% solution or gel of podofilox (podophyllotoxin). The medication is applied to the warts twice per day for three days followed by 4 days without treatment. Treatment should be continued up to three to four weeks or until the lesions are gone. Podofilox may also be applied every other day for a total of three weeks. Alternatively, a 5% cream of imiquimod (a substance that stimulates the body’s production of cytokines, chemicals that direct and strengthen the immune response) is likewise applied by the patient three times a week at bedtime, and then washed off with mild soap and water 6-10 hours later. The applications are repeated for up to 16 weeks or until the lesions are gone.

Only an experienced physician can perform some of the treatments for genital warts. These include, for example, placing a small amount of a 10%-25% solution of podophyllin resin on the lesions, and then, after a period of hours, washing off the podophyllin. The treatments are repeated weekly until the genital warts are gone. An 80%-90% solution of trichloroacetic acid (TCA) or bichloracetic acid (BCA) can also be applied weekly by a physician to the lesions. Injection of 5-fluorouracil epinephrine gel into the lesions has also been shown to be effective in treating genital warts.

Interferon alpha, a substance that stimulates the body’s immune response, has also been used in the treatment of genital warts. Treatment regimens require injections of interferon into the lesion every other day over a period of 8 to 12 weeks.

Alternative methods include cryotherapy (freezing the genital warts with liquid nitrogen) every one to two weeks, surgical removal of the lesions, or laser surgery. Laser surgery and surgical excision both require a local or general anesthetic, depending upon the extent of the lesions.

Treatment of precancerous changes (dysplasia) of the cervix related to HPV infection

Women who have evidence of moderate to severe precancerous changes in the uterine cervix require treatment to ensure that these cells do not become invasive cancer. In this case, treatment usually involves surgical removal or destruction of the involved tissue. Conization is a procedure that removes the precancerous area of the cervix using a knife, a laser, or a procedure known as LEEP (loop electrosurgical excision procedure, which uses an electric current passing through a thin wire that acts as a knife). Cryotherapy (freezing) or laser therapy may be used to destroy tissue areas that contain potentially precancerous changes.

Both people with HPV infection and their partners need to be counseled about the risk of spreading HPV and the appearance of the lesions. They should understand that the absence of lesions does not exclude the possibility of transmission and that condoms are not completely effective in preventing the spread of the infection. It is important to note that it is not known whether treatment decreases infectivity. Finally, female partners of men with genital warts should be reminded of the importance of regular Pap smears to screen for cervical cancer and precancerous changes in the cervix, since precancerous changes can be treated and reduce a woman’s risk of developing cervical cancer. Similarly, men should be informed of the potential risk of anal cancers, although it is not yet been determined how to best screen for or manage early anal cancer.

Recent research studies have led to the development of a vaccine against four common HPV types associated with the development of genital warts and cervical and anogenital carcinomas. This vaccine has received FDA approval for use in females between 9 and 26 years of age and confers immunity against HPV types 6, 11, 16 and 18. Another vaccine directed at HPV types 16 and 18 is currently being tested, and initial trials with the vaccine have shown that the HPV-16/18 vaccine is safe and induces a high degree of protection against HPV-16/18 infection. These encouraging results suggest that widespread vaccination for HPV types could begin in the near future.

Chancroid is an infection caused by the bacterium Hemophilus ducreyi, which is passed from one sexual partner to another. It begins in a sexually exposed area of the genital skin, most commonly the penis and vulva (the female external genital organs including the labia, clitoris, and entrance to the vagina). Chancroid starts out as a tender bump that emerges 3 to10 days (the incubation period) after the sexual exposure. The cells that form the bump then begin to die, and the bump becomes an ulcer (an open sore) that is usually painful. Often, there is an associated tenderness and swelling of the glands (lymph nodes) in the groin that normally drain lymph (tissue fluid) from the genital area; however, the painful ulcer and tender lymph nodes occur together in only about one-third of infections. Chancroid is common in developing countries but is a relatively rare cause of genital ulcers in the U.S.

A clinical diagnosis of chancroid (which is made from the medical history and physical examination) can be made if the patient has one or more painful ulcers in the genital area and tests are negative for syphilis or herpes. (The word chancroid means resembling a chancre, the genital ulcer that is caused by syphilis. Chancroid sometimes is called soft chancre to distinguish it from the chancre of syphilis that feels hard to the touch. The ulcer of chancroid also is painful, unlike the ulcer of syphilis that is painless.) The diagnosis of chancroid can be confirmed by a culture of the material from within the ulcer for the bacterium Hemophilus ducreyi. The clinical diagnosis justifies the treatment of chancroid even if cultures are not available.

Chancroid is almost always cured with a single oral dose of 1 gm of azithromycin (Zithromax) or a single injection of ceftriaxone (Rocephin). Alternative medications are ciprofloxacin (Cipro) or erythromycin, 500 mg taken three times per day by mouth for seven days. Whichever treatment is used, the ulcers should improve within seven days. If no improvement is seen after treatment, the patient should be reevaluated for causes of ulcers other than chancroid. HIV-infected individuals are at an increased risk for failing treatment for chancroid and should be observed closely to assure that the treatment has been effective.

A healthcare provider should evaluate anyone who has had sexual contact with a person with chancroid. Whether or not exposed individuals have an ulcer, they should be treated. Moreover, if the contact was 10 days or less before the onset of their partner’s ulcer, they should be treated.

Ectoparasitic infections are infections that are caused by tiny parasitic bugs, such as lice or mites. They are transmitted by close physical contact, including sexual contact. The parasites affect the skin or hair and cause itching.

Pediculosis pubis is an infection of the genital area caused by the crab louse (Phthirus pubis). The lice (commonly called crabs) are small bugs that are visible to the naked eye without the aid of a magnifying glass or microscope. The lice live on pubic hair (or any other hair) and are associated with itching.

The treatment for pubic lice is usually with a 1% cream rinse of permethrin that is applied to the affected area and washed off after 10 minutes. Alternative treatments include a 1% shampoo of lindane applied for four minutes before washing off or pyrethrins with piperonyl butoxide applied for 10 minutes before washing off. None of these treatments should be used for involvement near the eyes because they can be very irritating. The patient’s bedding and clothing should be machine-washed with hot water. All sexual partners within the preceding month should be treated for pubic lice and evaluated for other STDs.

Scabies is an ectoparasitic infection caused by a mite (known as Sarcoptes scabiei) that is not visible with the naked eye but can be seen with a magnifying glass or microscope. The parasites live on the skin and cause itching over the hands, arms, trunk, legs, and buttocks. The itching usually starts several weeks after exposure to a person with scabies and is often associated with small bumps over the area of itching. The itching from scabies is usually worse at night.

The standard treatment for scabies is a 5% cream of permethrin (Elimite), which is applied to the entire body from the neck down and then washed off after 8 to 14 hours. Treatment is repeated in one week. An alternative treatment is 1 ounce of a 1% lotion or 30 grams of cream of lindane, applied from the neck down and washed off after approximately eight hours. Unfortunately, itching may persist for up to two months after successful therapy. Since lindane can cause seizures when it is absorbed through the skin, it should not be used if skin is significantly irritated or wet, such as with extensive skin disease, rash, or after a bath. As an additional precaution, lindane should not be used in pregnant or nursing women or children younger than two years old.

Ivermectin (Stromectol) is a drug taken by mouth that has also been successfully used to treat scabies. The CDC recommends taking this drug at a dosage of 200 micrograms per kilogram body weight as a single dose, followed by a repeat dose two weeks later. While a patient my find that taking a drug by mouth is more convenient than application of the cream, ivermectin has a greater risk of toxic side effects than permethrin and has not been shown to be superior to permethrin in eradicating scabies.

As with pubic lice infection, both the bedding and clothing of an infected individual should be machine-washed in hot water. Finally, all sexual and close personal and household contacts within the month before the infection should be examined and treated if infection is found.

Infection with the human immunodeficiency virus (HIV) weakens the body’s immune system and increases the body’s vulnerability to many different infections, as well as the development of certain cancers.

HIV is a viral infection that is primarily transmitted by sexual contact or sharing needles, or from an infected pregnant woman to her newborn. Negative antibody tests do not rule out recent infection. Most (95%) people who are infected will have a positive HIV antibody test within 12 weeks of exposure.

Although there are no specific symptoms or signs that confirm HIV infection, many people will develop a nonspecific illness two to four weeks after they have been infected. This initial illness may be characterized by fever, vomiting, diarrhea, muscle and joint pains, headache, sore throat, and/or painful lymph nodes. On average, people are ill for up to two weeks with the initial illness. In rare cases, the initial illness has occurred up to 10 months after infection. It is also possible to become infected with the HIV virus without having recognized the initial illness.

The average time from infection to the development of symptoms related to immunosuppression (decreased functioning of the immune system) is 10 years. Serious complications include unusual infections or cancers, weight loss, intellectual deterioration (dementia), and death. When the symptoms of HIV are severe, the disease is referred to as the acquired immunodeficiency syndrome (AIDS). Numerous treatment options now available for HIV-infected individuals allow many patients to control their infection and delay the progression of their disease to AIDS.

Hepatitis B virus (HBV) is a virus that causes inflammation of the liver. Most people do not think of hepatitis as a sexually transmitted infection; however, one of the more common modes of the spread of viral hepatitis B is through intimate sexual contact. Sexual transmission is believed to be responsible for 30% of the cases worldwide. (Improved screening of donated blood has diminished the risk of getting hepatitis B from blood transfusion.) Complications from hepatitis B are responsible for 1 to 2 million deaths yearly.

Hepatitis B virus can cause both an initial (acute) and a chronic form of liver inflammation. The initial phase of infection lasts a few weeks, and in most people, the infection clears. People who recover from the initial infection develop immunity to the HBV, which protects them from future infection with this virus. Still, a small percent of individuals infected with HBV will develop chronic or long-lasting liver disease. These persons are potentially infectious to others. It is the chronic form of hepatitis B that is dangerous to women. Chronic hepatitis B is associated with cirrhosis of the liver , liver failure, and liver cancer.

Transmission of hepatitis B can occur during the early phase of infection or during the chronic carrier stage. Kissing and unprotected intercourse are methods of spreading this virus. While hepatitis does not affect the reproductive organs, a pregnant woman can transmit it to the fetus if she is infected during the pregnancy. The hepatitis B virus is transmitted to 80% of the fetuses in women that are infected during pregnancy. This is potentially dangerous, since infected infants have an 80% chance of developing the chronic form of the infection.

Only 50% of acute infections with the hepatitis B virus produce symptoms. The symptoms of hepatitis include yellow coloration of the skin or eyes (jaundice), fever, upper abdominal pain, generalized malaise, and nausea. In later stages, hepatitis B can cause edema (swelling of the legs) and ascites (fluid accumulation in the abdomen).

A highly effective vaccine that prevents hepatitis B is currently available. It is recommended that all babies be vaccinated against HBV beginning at birth, and all children under the age of 18 who have not been vaccinated should also receive the vaccination. Among adults, anyone who wishes to do so may receive the vaccine, and it is recommended especially for anyone whose behavior or lifestyle may pose a risk of HBV infection. Examples of at-risk groups include:

√ sexually active men and women;
√ illegal drug users;
√ health-care workers;
√ recipients of certain blood products;
√ household and sexual contacts of persons known to be chronically infected with hepatitis B;
√ adoptees from countries in which hepatitis B is common, such as Southeast Asia;
√ certain international travelers who may have sexual or blood exposures;
√ clients and employees of facilities for the developmentally disabled, infants and children;
√ patients with renal failure on hemodialysis.
The vaccine is given as a series of three injections in the muscle tissue of the shoulder. The second dose is administered one month after the first dose and the third dose is given five months after the second dose. In the event that a non-immunized individual (who would not have protective antibodies against HBV) is exposed to the genital secretions or blood of an infected person, the exposed person should receive purified hepatitis B immunoglobulin antibodies (HBIG) and initiate the vaccine series.

Liver tests in the blood become abnormal 1-10 days after infection with the virus. Hepatitis B then can be diagnosed by detecting antibodies against the virus and by blood tests that identify the virus in the blood.

Diagnosis of HBV infection involves blood tests to detect the hepatitis B surface antigen (HBsAg, the outer coat of the virus), hepatitis B surface antibody (HBsAb), and hepatitis B core antibody (HBcAb). If the HBsAb antibodies are in the blood, their presence indicates that the person has been exposed to the virus and is immune to future infection. Furthermore, this person cannot transmit the virus to others or develop liver disease from the infection. The HBcAb antibodies identify both past and current infection with the HBV. If the HbsAg antigen is in the blood, the person is infectious to others. There are also two possible interpretations to the presence of this antigen. In one, the person has been recently infected with HBV, may have acute viral hepatitis B, and will develop immunity in the coming months. In the other interpretation, the person is chronically infected with HBV, may have chronic hepatitis, and is at risk for developing the complications of chronic liver disease.

Hepatitis C is liver inflammation (hepatitis) that is caused by the hepatitis C virus (HCV). The HCV causes acute and chronic viral hepatitis C. Unlike hepatitis B, however, hepatitis C is infrequently transmitted sexually, so that it is unusual as an STD. It is primarily spread by exposure to infected blood, such as from sharing needles for drug use, piercing, tattooing, and occasionally sharing nasal straws for cocaine use. About 5% of babies born to women infected with HCV will also become infected with the virus. Sometimes there is no method of spread identifiable.

Most infected people have no symptoms, so a delayed or missed diagnosis is common. In contrast to HBV, with which chronic infection is uncommon, the majority (75%-85%) of people infected with hepatitis C develop chronic (long-term) infection. However, as is the case with hepatitis B, chronically infected individuals are infectious to others and are at an increased risk of developing severe liver disease and its complications, even if they have no symptoms.

Hepatitis C infection is diagnosed by using a standard antibody blood test. The antibody indicates an exposure to the virus at some time. Thus, the hepatitis C antibody is found in the blood during acute hepatitis C, after recovery from the acute hepatitis, and during chronic hepatitis C. Individuals with a positive antibody test can then be tested for evidence of virus in the blood by a test that detects the genetic material of the virus (called the polymerase chain reaction, or PCR). The PCR test rarely is needed to diagnose acute hepatitis C but sometimes can be helpful to confirm the diagnosis of chronic hepatitis C.

The most important fact to remember about sexually transmitted infections is that all of them are preventable. However, the risks of these infections are often downplayed and thus forgotten by many. The use of condoms can help decrease the risk of transmission of certain infections, but they do not prevent the transmission of many infections. There is truly no such thing as safe sex. Sex in the context of a monogamous relationship wherein neither party is infected with a STD is, however, considered safe.