HSV is a member of the family of viruses responsible for chicken pox, shingles, and infectious mononucleosis. The strain HSV-1 of this common virus is also responsible for cold sores, canker sores, and fever blisters that appear on the mouth. Primarily because of oral sex, HSV-1 has become increasingly responsible for the sores we think of in relation to genital herpes. Nevertheless, the related strain HSV-2 remains the leading cause of the problem. This strain has spread dramatically in the past several decades. Like all other viruses, it can't be cured, but there are drugs that can provide relief.

The virus which causes herpes lives in nerve cells at the bottom of the spine, and "creeps" to the surface once in a while to cause sores and blisters. In fact, herpes is named after the Greek word for "creeping." Recent studies have shown that most people with a herpes infection—probably as many as three-quarters—don't even know they have the disease because they have no symptoms: They never have any sores or blisters to alert them to the infection.

People who are unaware that they are infectious can unwittingly spread the disease. But even people who are aware of their infection can unknowingly spread it because viral particles are "shed," meaning they are present on the skin of the genitals, even when no sore or blister is apparent. This "asymptomatic" shedding happens prior to reappearance of the sore.

Because of its ease of transmission, the virus has become extremely common. Genital herpes is not a reportable disease, but an estimated 45 million Americans are infected with the virus. As many as 1 million new herpes infections occur each year.

Sporadic Signs of a Permanent Infection The hallmark of a herpes infection, these tiny blisters may break out for up to three weeks, then disappear on their own—only to return at unpredictable moments later on. Treatment with the drug Zovirax can ease the severity of an outbreak, but won't eradicate the infection. Because the herpes virus can be passed along even when there are no blisters in evidence, chances of contracting it are comparatively high: 200,000 new cases are reported each year.

• Risk factors
• Signs and symptoms
• Cause
• Incubation period
• Possible health effects
• Diagnosis
• Treatments
• Follow-up
• Prevention
• Pregnancy

• Risk factors: You are more likely to get herpes if you or your partner have multiple or casual sexual partners. The infection rate is higher among blacks (45 percent) than whites (17 percent). However, HSV-2 is on the increase fastest among white teens, who are nearly five times more likely to have herpes today than in the 1970s. Women are more at risk of infection than men (one out of four women are infected compared to one out of five men).

• Signs and symptoms: Many people with HSV have no signs or symptoms. If and when trademark sores appear, they can be on the vulva, in or around the vagina, in the anus, or on the cervix. Many women notice itching or a tingling sensation in the genital area before the sores appear. These are known as "prodromal symptoms." The first "outbreak" of a herpes infection is always the most severe, often lasting for three weeks or longer. The average length of time for a first episode is 12 days. Fever, headaches, swollen lymph glands, and sore muscles (especially in the legs) are common, in addition to the painful blisters. Some people will have one blister during an outbreak, while others will have many. Blisters deep in the vagina or cervix may not cause any pain. Recurrent episodes, during which the virus is reactivated, are milder and usually last about five days. For many people, the recurrences will occur less frequently over time.

• Cause: HSV is spread by skin to skin contact, especially during vaginal, anal, or oral intercourse. HSV-1 and HSV-2 are almost identical, so someone with a cold sore performing oral sex can give his or her partner genital herpes. It is thought that 30 percent of genital herpes is transmitted during oral sex. Once the virus enters the genital area, it quickly camps out in clumps of nerves at the base of the spine. It can lie dormant there for the rest of one's life, as it does in about 10 percent of all cases, or it can reappear sporadically. Many things can trigger recurrence of symptoms: surgery, illness, stress, fatigue, skin irritation (such as sunburn), dietary imbalance, menstruation, hormonal imbalance, pregnancy, or vigorous sexual intercourse. Sometimes no reason for an outbreak can be found.

• Incubation period: Symptoms usually start appearing within a week after infection if they are going to appear at all (remember, as many as 75 percent of people with HSV may be asymptomatic.) However, symptoms have been known to start one day to 26 days after exposure to the virus.

• Possible health effects: One complication from HSV is very rare and easily avoided: accidentally spreading the infection to the eyes. This can occur if you should happen to rub your eyes or put in contact lenses after touching an HSV sore. The herpes virus is easily killed with soap and water, though, so an eye infection can be avoided through stringent hygiene during outbreaks. Although an association between herpes and cervical cancer has not been established, women with the virus should have regular Pap tests because of their increased risk of other infections such as HPV.

• Diagnosis: It is important to see your doctor while symptoms are still present, because diagnosis is made by viewing sores and by taking a sample from the sore to look at under a microscope. Blood tests that detect antibodies to HSV are also reliable. Three of these blood tests are "type-specific"—meaning they can tell whether the problem is caused by HSV-1 or HSV-2. Identifying the specific culprit is important because the types act differently. For example, HSV-1 recurs less frequently than HSV-2.

• Treatments: Although nothing is available to rid the body of a virus, there are three drugs that can alter the herpes virus' ability to cause damage once it comes out of its hiding place in the nerve ganglia. Zovirax is the most frequently prescribed drug for an initial herpes outbreak. Duration of symptoms can be reduced from nine days to about five; healing time is reduced from about three weeks to about two weeks; and viral shedding can be cut down from 10 days to about two. The topical cream form of Zovirax can be effective for the initial outbreak, but rarely works well for recurrences. Taking oral Zovirax for recurrent outbreaks, while it can still be effective, has a less significant impact for some people. Your doctor has a choice of the following oral drug regimens to treat an initial herpes outbreak:

• famciclovir (Famvir), 125 milligrams taken twice a day for 5 days, or

• valacyclovir (Valtrex), 1,000 milligrams taken twice a day for 7 to 10 days

If you are aware enough of your body and can know when a herpes attack is about to strike, taking one of these drugs as soon as possible can help lessen the severity of recurrences. Usually the initial warning symptoms—muscle aches, genital itching and tingling—will alert you.

If you have had one outbreak of genital herpes, you are likely to experience others. For recurrent outbreaks, the doctor can prescribe:

• acyclovir, 200 milligrams taken 5 times a day for 5 to 10 days, or 400 milligrams taken 3 times a day for 5 to 10 days (start treatment within 2 days of onset), or

• famciclovir, 500 milligrams taken twice a day for 5 to 10 days (start treatment within 6 hours of onset), or

• valacyclovir, 1,000 milligrams taken twice a day for 5 to 10 days (start treatment within 24 hours of onset)

This conservative therapeutic approach can reduce shedding time by almost half, from nearly four days to slightly over two days.

Taking antivirals only at the onset of an outbreak is referred to as "episodic" therapy. If you suffer from many outbreaks a year —once every month or two—or if having herpes is causing you great psychological distress, you might consider "suppressive" therapy. Dosage guidelines for this form of treatment are:

• acyclovir, 400 milligrams twice daily for a year, or

• famciclovir, 250 milligrams twice daily for a year, or

• valacyclovir, 500 to 1,000 milligrams once a day for a year

Using an antiviral medication in this way reduces outbreaks by at least 75 percent among patients with frequent outbreaks. It has not, however, been shown to cut down on viral shedding, so you could still pass the disease to a partner, and the outbreak will resume when therapy stops. A trial is underway to see if suppressive therapy can actually reduce transmission of herpes

There is varying opinion on how long a person should stay on suppressive therapy. The U.S. Food and Drug Administration currently recommends only one year, although studies have shown that patients do well with three or even seven years. Additionally, suppressive therapy is expensive, costing between $2 and $4 a day. Talk with your doctor to decide what is best for you.

There is some evidence that zinc and vitamins A and C can enhance the immune system's response to herpes. Aloe vera extract and other topical ointments may speed healing of the sores. However, the effectiveness of these natural therapies has yet to be definitively proven.

• Follow-up: If an initial outbreak warns that you have herpes, tell all sex partners from the prior three weeks. If you find out some other way, from a blood test for example, you may not know when you were infected. It is up to you and your doctor to decide which partners to tell. It is also up to you to decide when and if to tell a new partner about your infection.

• Prevention: Don't assume that you're no longer contagious when symptoms subside. The high rate of herpes infection is largely due to the fact that the virus is shed between outbreaks just as often as when there are sores. The key to prevention is use of condoms and spermicides (which kill the herpes virus). Strangely, in long-standing marriages where only one partner is infected, the other often stays herpes-free.

HSV-1 and HSV-2 can easily migrate through the body, so oral sex should be avoided when there is an active sore on the mouth or genitals.

• Pregnancy: The most serious known complication of herpes threatens infants born to HSV-infected mothers. An HSV-infected baby is at risk for blindness, brain damage, and even death. Fortunately, the risk of transmitting the infection to a newborn at birth is low, even for women who have long-standing, recurrent outbreaks. If the baby does get infected (a less than 3 percent chance for women with recurrent infections), acyclovir or valacyclovir will probably be used as treatment. HSV also increases the risk of miscarriage or premature labor and delivery.

The group at highest risk are women who acquire HSV late in their pregnancy, particularly those who have no immune defense to the virus (developed from having had diseases like chickenpox, or cold sores, etc.). Indeed, one-third to one-half of women who acquire genital herpes near the time of delivery transmit the virus to their infant.

Women with immune defense, which can be measured by antibodies to HSV in the blood, pass immunity to the baby through the placenta during the third trimester of pregnancy. Infants born to HSV-infected and antibody-carrying mothers are thus protected from the disease should they come into contact with it as they pass through the birth canal. Most HSV-infected women can have normal, vaginal deliveries. Having an active sore at the time of delivery will warrant a cesarean delivery.

If you are pregnant and either have HSV or have sex with an infected partner during your pregnancy, or if you or your partner have sex with more than one partner during your pregnancy, be sure to tell your doctor. He or she will then test to see if you are shedding the virus when it comes time to deliver the baby.

None of the three available drugs has been thoroughly studied for use by pregnant women, so your doctor will probably advise stopping suppressive or episodic therapy during pregnancy. If you develop an initial outbreak during pregnancy, however, the doctor is likely to prescribe acyclovir. This drug—the most extensively studied of the three—doesn't appear to increase the risk of birth defects. There is too little experience on the other two drugs to make the same claim.

Help with Herpes Having trouble paying for acyclovir treatment? Glaxo Wellcome, the makers of Zovirax, offers a patient assistance program for hardship cases. Request an application by calling 1-800-722-9294.