Genital HerpesAugust 1992 Genital
herpes is a contagious viral infection that
affects an estimated 23 percent of adult
Americans. Each year, as many as 500,000 new
cases are believed to occur. The infection is
caused by the herpes simplex virus (HSV).
There are two types of HSV, and both can
cause the symptoms of genital herpes. HSV
type 1 most commonly causes sores on the lips
(known as fever blisters or cold sores), but
it can cause genital infections as well. HSV
type 2 most often causes genital sores, but
it also can infect the mouth.
HSV 1 and 2 can both produce sores in and around the vaginal area, on the penis, around the anal opening, and on the buttocks or thighs. Occasionally, sores also appear on other parts of the body where broken skin has come into contact with HSV. The virus remains in certain nerve cells of the body for life, causing periodic symptoms in some people. Genital herpes infection usually is acquired by sexual contact with someone who has an outbreak of herpes sores in the genital area. People with oral herpes can transmit the infection to the genital area of a partner during oral-genital sex. Herpes infections also can be transmitted by a person who is infected with HSV but has no noticeable symptoms. The virus is spread only rarely, if at all, by contact with objects such as a toilet seat or hot tub.
SymptomsWithin a few days, sores (also called lesions) appear at the site of infection. Lesions also can occur on the cervix in women or in the urinary passage in men. These small red bumps may develop into blisters or painful open sores. Over a period of days, the sores become crusted and then heal without scarring. Other symptoms that may accompany a primary episode of genital herpes can include fever, headache, muscle aches, painful or difficult urination, vaginal discharge, and swollen glands in the groin area.
RecurrencesIn genital herpes, after invading the skin or mucous membranes, the virus travels to the sensory nerves at the end of the spinal cord. Even after the skin lesions have disappeared, the virus remains inside the nerve cells in an inactive, latent state. In most people, the virus will reactivate from time to time. It travels along the nerves to the skin, where it multiplies on the surface at or near the site of the original herpes sores, causing new sores to erupt. It also can reactivate without causing any visible sores. At these times, small amounts of the virus may be shed at or near sites of the original infection, in genital secretions, or from barely noticeable lesions. This shedding is infrequent, however, and usually lasts only a day, but it is sufficient to infect a sex partner. The symptoms of recurrent episodes usually are milder than those of the first episode and typically last about a week. A recurrent outbreak may be signaled by a tingling sensation or itching in the genital area, or pain in the buttocks or down the leg. These are called prodromal symptoms, and, for some people, they can be the most painful and annoying part of a recurrent episode. Sometimes only the prodrome is present and no visible sores develop. At other times, blisters appear that may be very small and barely noticeable, or they may break into open sores that crust over and then disappear. The frequency and severity of the recurrent episodes vary greatly. While some people recognize only one or two recurrences in a lifetime, others may experience several outbreaks a year. The number and pattern of recurrences often change over time for an individual. Scientists do not know what causes the virus to reactivate. Although some people with herpes report that their recurrences are brought on by other illness, stress, or menstruation, recurrences often are not predictable. In some cases, exposure to sunlight is associated with recurrences.
DiagnosisThe sores of genital herpes in its active stage are usually visible to the naked eye. Several laboratory tests may be needed, however, to distinguish herpes sores from other infections. The most accurate method of diagnosis is by viral culture, in which a new sore is swabbed or scraped and the sample is added to a laboratory culture containing healthy cells. When examined under a microscope after one to two days, the cells show changes that indicate growth of the herpes virus. A newer, more rapid, but somewhat less accurate way of diagnosing herpes involves detection of viral protein components in lesion swabs. These tests should be done when the sores first appear to ensure the most reliable results. Other laboratory tests also are available to physicians. It is important to note that because clinicians commonly fail to detect HSV in an active sore, a negative virus culture does not always mean that a person is not infected with the virus. A blood test cannot determine whether a person has an active genital herpes infection. A blood test, however, can detect antibodies to the virus, which indicate that the person has been infected with HSV at some time and has produced antibodies to it. (Antibodies are proteins made by a person's immune system to fight infections.) Unlike antibodies to some other viruses, however, antibodies to HSV do not totally protect an individual against another infection with a different strain or a different type of herpes virus, nor do they prevent a reactivation of the latent virus. Antibody tests are the best way to determine if a person is an HSV carrier. The standard blood tests only reliably indicate whether a patient has had a herpes infection, not the type of HSV. New blood tests have been developed that can distinguish whether a person has had prior type 1 or type 2 infection, or both. However, these tests are available mainly in research hospitals and are not used routinely in the doctor's office.
TreatmentDuring an active herpes episode, whether primary or recurrent, it is important to follow a few simple steps to speed healing and to avoid spreading the infection to other sites of the body or to other people:
Researchers have shown that the oral form of acyclovir (Zovirax®) is a superior and safe treatment that helps patients with first or recurrent episodes of genital herpes. The oral form of the drug is taken five times a day and markedly shortens the course of the first episode and limits the severity of recurrences, particularly if taken within 24 hours of onset of symptoms. People who have very frequent recurrent episodes of the disease can take oral acyclovir twice daily for up to one year at a time to suppress the virus' activity and prevent most recurrences. After a year, it is reasonable to stop the medication and only to restart it if frequent recurrences resume. Acyclovir is not a cure for herpesthe virus remains in the body; but while taken regularly, the medicine interferes with the virus' ability to reproduce itself. The U. S. Food and Drug Administration recently approved two new drugs, famciclovir (Famvir®) and valacyclovir (Valtrex®), to treat recurrent episodes of genital herpes. Famciclovir also has been approved for use in suppressing viral activity and preventing recurrences. These two drugs can be taken less frequently than acyclovir, i.e., three times a day for recurrent episodes and twice daily to help stop further recurrences.
ComplicationsGenital herpes infections do not cause permanent disability or long-term damage in healthy adults. In people who have suppressed immune systems, however, HSV episodes can be long-lasting and unusually severe. A pregnant woman who develops a first episode of genital herpes can pass the virus to her fetus and may be at higher risk for premature delivery. Half of the babies infected with herpes either die or suffer neurologic damage. A baby born with herpes can develop encephalitis (inflammation of the brain), severe rashes, and eye problems. Acyclovir can greatly improve the outcome for babies with neonatal herpes, particularly if they are treated immediately. With early detection and treatment, most of these serious complications can be lessened. The newborn's chances of infection depend on whether the mother is having a recurrent or a first outbreak. If the mother is having her first outbreak near or at the time of a vaginal birth, the baby's risk of infection is approximately one in three. If the outbreak is a recurrence, the baby's risk is very low (less than one in 30). Because of the danger of infection to the baby, however, the physician will perform a cesarean section if herpes lesions are detected in or near the birth canal during labor. Some physicians also perform a viral culture at the time of delivery to detect viral shedding in women known to have had genital herpes outbreaks in the past. It is important to remember that most women with genital herpes do not have signs of active infection with the virus at delivery. In the absence of symptoms of active infection, their babies can be safely delivered vaginally.
HSV and AIDSGenital herpes, like other genital ulcer diseases, increases the risk of acquiring HIV, the virus that causes AIDS, by providing an accessible point of entry for HIV. Also, persons with HIV can have severe herpes outbreaks, and this may help transmit both herpes and HIV infections to others.
PreventionPeople with early signs of a herpes outbreak or with visible sores should not have sexual intercourse until the sores have healed completely. Between outbreaks, using condoms during sexual intercourse is the best way to prevent infecting a partner.
ResearchScientists supported by NIAID are concentrating their efforts in several areas of investigation, including determining what causes the virus to reactivate, finding better treatments to prevent transmission and recurrence of HSV, and developing and testing a safe and effective vaccine. Other scientists have developed an experimental test that can be used to screen blood samples for evidence of herpes infection and can accurately distinguish type 1 from type 2 infections. Rapid diagnostic tests have been developed that can detect active virus in a pregnant woman at the time of delivery. These tests may be able to identify exposed infants who should be observed carefully or receive immediate care.
Emotional SupportRecurrences of genital herpes can be distressing, inconvenient, and sometimes painful. Concern about transmitting the disease to others and disruption of sexual relations during active outbreaks of the sores can affect personal relationships. Patients can cope with and manage the disease effectively, however, with proper counseling, improved treatments, and preventive measures. Counseling and help for those who have genital herpes is often available from local or state health departments. In addition, the American Social Health Association operates a hotline for questions and concerns:
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This article was provided by U.S. National Institute of Allergy and Infectious Diseases. |
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