Genital herpes is a sexually transmitted infection (STI) caused by the herpes simplex virus (HSV).
This article focuses on HSV type 2 (HSV-2) infection.
Herpes – genital; Herpes simplex – genital; Herpesvirus 2; HSV-2
Causes, incidence, and risk factors
Genital herpes affects the skin or mucous membranes of the genitals. It caused by the herpes simplex virus (HSV). HSV is spread from one person to another during sexual contact.
- HSV-2 most often causes genital herpes. HSV-2 can be spread through secretions from the mouth or genitals.
- HSV-1 usually affects the mouth and lips and causes cold sores or fever blisters. However, it can spread from the mouth to the genitals during oral sex. For more information on HSV-1, see: Herpes labialis
You may become infected with herpes if your skin, vagina, penis, or mouth comes into contact with someone who already has herpes.
You are most likely to get herpes if you touch the skin of someone who has herpes sores, blisters, or a rash. However, the herpes virus can still be spread even when no sores or other symptoms are present. Sometimes, the person does not even know they are infected.
Genital HSV-2 infections are more common in women than men.
Many people with genital herpes never have sores, or they have very mild symptoms that go unnoticed or are mistaken 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 days to 2 weeks of being infected.
General symptoms may include:
- Decreased appetite
- General sick feeling (Malaise)
- Muscle aches in the lower back, buttocks, thighs, or knees
- Swollen and tender lymph nodes in the groin during an outbreak
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:
- 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 later. It is usually less severe and goes away sooner than the first outbreak. Over time, the number of outbreaks may decrease.
Once you have HSV-2, the virus hides within nerve cells and remains in the body. It can remain “asleep” (dormant) for a long time.
The virus can “wake up” (reactivate) at any time. This may be triggered by:
- Genital irritation
- Physical or emotional stress
Some people have genital herpes attacks only once a year, while others have them so often the symptoms never seem to go away. Repeated attacks are generally milder in men.
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.
See: Herpes genital – support group
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 genital herpes infection when they give birth may pass the infection to their baby.
- The risk of passing the infection to the baby is highest if the mom first becomes infected with genital herpes during pregnancy. The risk for severe infection in the baby is much lower in recurrent outbreaks.
- Babies of women who become infected during pregnancy are at risk for premature birth. The baby may develop brain infection (meningitis, encephalitis) , chronic skin infeciton, severe developmental delays, or death.
- Women with a history of genital herpes who have occasional or no outbreaks rarely spread the infection to their babies.
The herpes virus may spread to other parts of the body, including the brain, eyes, esophagus, liver, spinal cord, or lungs. These complications often develop in people who have a weakened immune system due to HIV or certain medications.
You are more likely to get HIV if you have an active genital herpes infection and have sex with someone who is HIV positive.
Calling your health care provider
Call 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.
The best way to avoid genital herpes is to avoid all sexual contact, including oral sex.
Being in a long-term, mutually monogamous relationship with someone who has been tested and has never been infected with the virus can also help reduce your chances of becoming infected.
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.
Anyone who has genital herpes should tell their partner that they have the disease, even if they do not have symptoms.
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