Genital herpes is a sexually transmitted viral infection affecting the skin or mucous membranes of the genitals.
Herpes - genital; Herpes simplex - genital; Herpesvirus 2; HSV-2
Causes, incidence, and risk factors
Genital herpes is caused by two viruses:
- Herpes simplex virus type 2 (HSV-2)
- Herpes simplex virus type 1 (HSV-1)
Herpes simplex virus type 2 (HSV-2) causes most cases of genital herpes. HSV-2 can be spread through secretions from the mouth or genitals.
Herpes simplex virus type 1 (HSV-1) most often causes herpes infections of the mouth and lips (commonly called cold sores or fever blisters). HSV-1 can spread from the mouth to the genitals during oral sex.
Herpes simplex virus (HSV) is spread from one person to another during sexual contact. You may be infected with herpes when your skin, vagina, penis, or mouth comes into contact with someone who already has herpes.
Herpes is most likely to be transmitted by contact with the skin of an infected person who has visible sores, blisters, or a rash (an active outbreak), but you can also catch herpes from an infected person's skin when they have NO visible sores present (and the person may not even know that he or she is infected), or from an infected persons mouth (saliva) or vaginal fluids.
Because the virus can be spread even when there are no symptoms or sores present, a sexual partner who has been infected with herpes in the past but has no active herpes sores can still pass the infection on to others.
Genital HSV-2 infections is more common in women (approximately 1 of every 4 women is infected) than it is in men (nearly 1 of every 8 men is infected).
Many people with HSV-2 infection never have sores, or they have very mild symptoms that they do not even notice or mistake for insect bites or another skin condition.
If signs and symptoms do occur during the first outbreak, they can be quite severe. This first outbreak usually happens within 2 weeks of being infected.
Generalized or whole-body (systemic) symptoms may include:
- Decreased appetite
- General sick feeling (Malaise)
- Muscle aches in the lower back, buttocks, thighs, or knees
Genital symptoms include the appearance of small, painful blisters filled with clear or straw-colored fluid. They are usually found:
- In women: on the outer vaginal lips (labia), vagina, cervix, around the anus, and on the thighs or buttocks
- In men: on the penis, scrotum, around the anus, on the thighs or buttocks
- In both sexes: on the tongue, mouth, eyes, gums, lips, fingers, and other parts of the body
- Before the blisters appear, the person may feel the skin tingling, burning, itching, or have pain at the site where the blisters will appear
- When the blisters break, they leave shallow ulcers that are very painful. These ulcers eventually crust over and slowly heal over 7 - 14 days or more
Other symptoms that may occur include:
- Enlarged and tender lymph nodes in the groin during an outbreak
- Painful urination
- Women may have vaginal discharge or, occasionally, be unable to empty the bladder and require a urinary catheter
A second outbreak can appear weeks or months after the first. It is almost always less severe and shorter than the first outbreak. Over time, the number of outbreaks tends to decrease.
Once a person is infected, however, the virus hides within nerve cells and remains in the body. The virus can remain "asleep" (dormant) for a long period of time (this is called latency).
The infection can flare-up or reactivate at any time. Events that can trigger latent infection to become active and bring on an outbreak include:
- Genital irritation
- Physical or emotional stress
Attacks can recur as seldom as once per year, or so often that the symptoms seem continuous. Recurrent infections in men are generally milder and shorter than those in women.
Signs and tests
Tests can be done on skin sores or blisters to diagnose herpes. These tests are most often done when someone has a first outbreak and when a pregnant women develops genital herpes symptoms.
- Culture of fluid from a blister or open sore may be positive for herpes simplex virus. The herpes simplex virus can in the culture in 2-3 days. It is most useful during the first outbreak.
- A test called PCR performed on fluid from a blister shows small amounts of DNA. It is the most accurate test to tell whether the herpes virus is present in the blister.
- Blood tests check for antibody levels to the herpes virus. These blood tests can identify whether someone has ever been infected with the herpes virus, even between outbreaks. It may be positive even if they've never had an outbreak.
Genital herpes cannot be cured. However, antiviral medication can relieve pain and discomfort during an outbreak by healing the sores more quickly. These drugs appear to help during first attacks more than they do in later outbreaks. Medicines used to treat herpes include acyclovir, famciclovir, and valacyclovir.
For repeat outbreaks, start the medication as soon as the tingling, burning, or itching begins, or as soon as you notice blisters.
People who have many outbreaks may take these medications daily over a period of time. This can help prevent outbreaks or shorten their length. It can also reduce the chance of giving herpes to someone else.
Pregnant women may be treated for herpes during the last month of pregnancy to reduce the chance of having an outbreak at the time of delivery. If there is an outbreak around the time of delivery, a C-section will be recommended to reduce the chance of infecting the baby.
Possible side effects from herpes medications include:
- Nausea and vomiting
Home care for herpes sores:
- Do NOT wear nylon or other synthetic pantyhose, underwear, or pants. Instead, wear loose-fitting cotton garments
- Gentle cleansing with soap and water is recommended.
- Taking warm baths may relieve the pain (afterward, keep the blisters dry)
If one of the sores develops an infection from bacteria, ask your doctor if you need an antibiotic.
Once you are infected, the virus stays in your body for the rest of your life. Some people never have another episode, and others have frequent outbreaks.
In most outbreaks, there is no obvious trigger. Many people, however, find that attacks of genital herpes occur with the following conditions:
- General illness (from mild illnesses to serious conditions, such as operations, heart attacks, and pneumonia)
- Immunosuppression due to AIDS or medication such as chemotherapy or steroids
- Physical or emotional stress
- Trauma to the affected area, including sexual activity
In people with a normal immune system, genital herpes remains a localized and bothersome infection, but is rarely life-threatening.
Pregnant women who have an active herpes infection on their genitals or in their birth canal when they deliver may pass the infection to their newborn infant.
- The risk of passing the infection to the baby is highest if the mom first becomes infected with herpes during pregnancy. Babies of women who become infected during pregnancy are at risk for premature birth. The baby may develop develop brain infection (meningitis, encephalitis) , chronic skin infeciton, severe developmental delays, or death.
- The risk for severe infection in the baby is lower in recurrent outbreaks, with the highest risk in women experiencing an outbreak at the time of delivery.
- Women with a history of herpes but who only have occasional or no outbreaks rarely transmit the infection to their babies.
Some peole may develop severe herpes infections that involve the brain, eyes, esophagus, livere, spinal cord, or lungs. These complications often develop in people who have a weakened immune system, AIDS, are undergoing chemotherapy or radiation therapy, or who take high doses of cortisone.
Someone with an active herpes infection who has sexual contact with someone who is HIV positive is more likely to contract HIV infection themselves.
Calling your health care provider
Call for an appointment with your health care provider if you have any symptoms of genital herpes, or if you develop fever, headache, vomiting, or widespread symptoms during or after an outbreak of herpes. Also call if you are unable to urinate.
The best way to avoid getting genital herpes is to avoid all sexual contact, including oral sex. Next best is being in a long-term, mutually monogamous relationshipw with someone who has been tested and is not, and never has been, infected with herpes.
Condoms remain the best way to protect against catching genital herpes during sexual activity with someone who is infected. Using a condom correctly and consistently will help prevent the spread of the disease.
- Only latex condomes will work to prevent infection. Animal membrane (sheepskin) condoms won't work because the virus can go right through them.
- The female condom has been tested and shown to reduce the risk of trasmitting herpes, as well.
- A latex condom should be used during ALL sexual contact, even if the infected person does not have any sores or blisters at that time.
In addition, people with genital herpes who don't have any current symptoms should tell their partner that they have the disease.
Vaccines against herpes have been developed but are still experimental.
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Reviewed By: Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Redmond, WA; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.