Sexually transmitted infections can also be caused by viruses. Once a virus invades a body cell, it is able to reproduce itself, so a person will have the virus for the rest of his or her life. Viruses can live in the body, and, although a person may not experience symptoms, he or she is still infected with the virus. We will now discuss herpes, human papillomavirus, and viral hepatitis, and later in this chapter we will explore the human immunodeficiency virus and AIDS.

Viral Infections: Herpes, Human Papillomavirus, and Hepatitis

Herpes

Herpes (herpes simplex, herpes genitalis) is caused by an infection with the herpes simplex virus (HSV). Typically the virus prefers to infect the mouth and face (herpes simplex I, or HSV-1), or the genitals (herpes simplex II, or HSV-2), where it causes sores to appear. HSV-1 and HSV-2 are usually transmitted through different routes; however, once infected, the signs and symptoms they cause can overlap (Whitley & Roizman, 2001). If the virus infects a less preferred site, such as an HSV-1 infection of the genitals or an HSV-2 infection of the mouth and face, the symptoms are usually less severe.

HSV-1 and HSV-2 are contained in the sores that the virus causes, but they are also released between outbreaks from the infected skin (often referred to as “viral shed­ding”). Because of this, the virus can be transmitted even when the infected partner doesn’t have any active symptoms (Wald et al., 2000). A person who engages in unpro­tected sexual activity (vaginal intercourse or anal sex) with a partner who is infected with HSV-2 will most probably become infected with a genital HSV-2 infection. A per­son who receives oral sex from a person infected with HSV-1 will most likely become in­fected with a genital HSV-1 infection.

It is possible for people who are infected with HSV to reinfect themselves on an­other part of their body. For instance, if a woman with HSV-1 touches an open lesion and then rubs another mucosal area, such as the mouth or genitals, she may autoinocu- late herself. She could also transmit HSV to her partner’s genitals in this manner.

Pregnant mothers can pass the herpes virus on to their infants in several ways. The most common method of infection is during delivery. However, transmission can also occur while the baby is in the uterus or directly following birth.

Incidence The herpes simplex virus II is one of the most common STIs in the United States today, with as many as 1 million people becoming infected each year (Weinstock et al., 2004). It is estimated that approximately 45 million people, age 12 and older, have genital herpes (Centers for Disease Control and Prevention, 2005d). However, infection rates are higher than reported because the majority of people with genital herpes have not been diagnosed (Centers for Disease Control and Prevention, 2002a).

 

herpes

A highly contagious viral infection that causes eruptions of the skin or mucous membranes.

 

herpes simplex virus (HSV)

The virus that causes herpes.

 

herpes simplex I (HSV-I)

A viral infection that causes cold sores on the face or lips.

 

herpes simplex II (HSV-2)

A viral infection that is sexually transmitted and causes genital ulcerations.

 

viral shedding

The release of viral infections between out­breaks from infected skin.

 

autoinoculate

To cause a secondary infection in the body from an already existing infection.

 

Подпись: I prodromal phase The tingling or burning feeling that precedes the development of herpes blisters. Подпись:Viral Infections: Herpes, Human Papillomavirus, and HepatitisWe do know that rates of genital herpes are higher in women, mainly due to the fact that male-to-female routes of transmission are more efficient than female-to-male routes. It is estimated that 1 in 4 women and 1 in 5 men have genital herpes (Centers for Disease Control and Prevention, 2005d). Herpes is also more common among African Americans (46%) than among Caucasians. Oral herpes is fairly common today. In fact, by the age of 5, it is estimated that more than 35% of African American children and 18% of Caucasian children are infected with HSV-1 (Whitley & Roizman, 2001). This is probably a result of kissing from HSV-1-infected relatives and friends.

Symptoms The first symptoms of herpes usually appear within 4 days after infec­tion, but they can appear anywhere from 2 to 12 days later. However, the majority of those infected with HSV-1 and HSV-2 do not experience any noticeable symptoms (Whitley & Roizman, 2001). If a person does develop HSV sores, the first occurrence is generally the most painful. Overall, women tend to have more severe symptoms with HSV-2 than men.

At the onset, there is usually a tingling or burning feeling in the affected area, which can grow into an itching and a red, swollen appearance of the genitals (this period is of­ten referred to as the prodromal phase). The sores usually last anywhere from 8 to 10 days, and the amount of pain they cause can range from mild to severe. Pain is usually most severe at the onset of the infection and improves thereafter. Depending on the amount of pain, urination may be difficult. Small blisters may appear externally on the vagina or penis. The blisters, which are usually red and sometimes have a grayish center, will eventually burst and ooze a yellowish discharge. As they begin to heal, a scab will form over them. Other symptoms of HSV include a fever, headaches, pain, itching, vagi­nal or urethral discharge, and general fatigue. These symptoms peak within 4 days of the appearance of the blisters. A few patients with severe symptoms require hospitalization.

The frequency and severity of recurrent episodes of herpes depend on several things, including the amount of infectious agent, the severity of the infection, the type of her­pes, and the timing of treatment (Kroon, 1990). Over time the frequency of recurrent outbreaks diminishes (Centers for Disease Control and Prevention, 2005d).

Psychological reactions to herpes outbreaks can include anxiety, guilt, anger, frustra­tion, helplessness, a decrease in self-esteem, and depression (Dibble & Swanson, 2000). Persons with supportive partners and social relationships tend to do better psychologically. In addition, those who receive psychological support services experience a greater reduction in recurrent episodes of herpes and an improvement in their emotional health (Swanson et al., 1999). Physical and emotional stress may increase the likelihood of recurrent episodes. People who have been infected with the herpes virus are advised to get plenty of sleep, to eat and exercise properly, and to reduce alcohol intake, cigarette smoking, and stress.

Recent research reveals that people who are infected with HSV-2 are at greater risk for acquiring HIV if they engage in unprotected sexual intercourse with someone who is HIV-positive, because the herpes blisters facilitate the transmission of HIV (Centers for Disease Control and Prevention, 2005d).

Viral Infections: Herpes, Human Papillomavirus, and Hepatitis

HSV-2 infection in women can cause blisters on the vulva, vagina, or anyplace the virus entered the body.

Diagnosis The presence of blisters caused by the herpes virus is often enough to diagnose the disease. Oftentimes, however, healthcare providers will take a scraping of the blisters to evaluate for the presence of HSV (Whitley & Roizman, 2001). No tests for the detection of HSV-1 or HSV-2 are 100% accurate because tests depend on the amount of infectious agent and the stage of the disease. Success rates for detecting HSV – 2 antibodies vary from 80% to 98%, and there are high false negative results, mainly due to the fact that tests are performed too early.

Treatment There is no cure for infection with the herpes virus. Once infected, a person will always carry the virus in his or her body. The standard therapy for HSV in­fection today is antiviral drugs (Balfour, 1999). Aciclovir, Valacyclovir, Famciclovir, and Penciclovir are all antiviral drugs that shorten the duration of outbreaks, prevent com­plications, and reduce viral shedding (Corey et al., 2004; Sacks et al., 2005). Topical, oral, or injected antiviral drugs can all be given, depending on the site of infection. Patients with frequent outbreaks are often put on suppressive or antiviral therapy to sup­press or reduce the frequency of recurrences (Wald, 1999; Whitley & Roizman, 2001). Antiviral therapy can significantly reduce sexual transmission of the virus (Patel, 2004).

Natural remedies for herpes outbreaks include applying an ice pack to the affected area during the prodromal phase and applying cooling or drying agents such as witch hazel. Increasing intake of foods rich in certain amino acids, such as L-lysine, which in­cludes fish or yogurt, and decreasing the intake of sugar and nuts (which are high in argi­nine) may also help reduce recurrences (Griffith et al., 1987; Vukovic, 1992). Lysine can also be purchased from the vitamin section of any drugstore.

Подпись: ■r ReviewQuestion Explain the incidence, symptoms, ^diagnosis, and treatment of the herpes simplex virus, and differentiate between HSV-1 and HSV-2. A vaccine for genital herpes (HSV-2), Simplirix, developed by SmithKline Beecham, has so far proved effective (Weibley, 2001). Although not yet approved by the FDA, this vaccine appears to be effective only for women who have not already been in­fected with HSV-2 and have never had HSV-1, but unfortunately this vaccine has not shown effectiveness in men. Other vaccines for HSV are currently in clinical trials, and these will be available to a wider percentage of people.

Viral Infections: Herpes, Human Papillomavirus, and HepatitisQuestion: Because herpes is not curable, when people are in their "downtime" between flare-ups, can they still transmit it?

Although many people believe that the herpes virus cannot be trans­mitted if there are no active lesions, there is now evidence that it can be transmitted even in the absence of active lesions (Boselli et al., 2005; Whitley & Roizman, 2001). Herpes simplex viruses are often asymptomatic, and therefore men and women who are infected with HSV-2 should al­ways use condoms so that they do not infect their partners.