Genital Herpes
Genital herpes is a viral infection. At least 8 in 10 people with the genital herpes virus do not know that they are infected. You catch it by having intimate (usually sexual) contact with someone who has the virus. In between episodes, the virus remains in your nerve system and can be reactivated from time to time to give you symptoms.
Genital herpes symptoms
The first time you are infected with genital herpes simplex it is called the primary infection. This may, or may not, cause symptoms (described below). Following a primary infection, the virus is not cleared from the body but lies inactive (dormant) in a nearby nerve. In some people, the virus 'activates' from time to time and travels down the nerve to the nearby skin. This causes recurrent symptoms of genital herpes if the primary infection was in the genitals, or recurrent cold sores if the primary infection was around the mouth.
It is common not to develop any symptoms
Most people never develop any symptoms when they are infected with the virus. At least 8 in 10 people with genital herpes simplex virus (HSV) do not know that they are infected. Or, they only have a short bout of very mild symptoms which is not recognised as genital herpes. For example, just a slight area of itch or a small red area which soon goes. In such people, the virus stays inactive in the root of a nerve that supplies the genitals, but never causes recurrent episodes of symptoms.
However, even people who do not develop symptoms may, on occasions, have virus in their genital area and therefore be infectious to sexual partners. In fact, this is how many genital herpes simplex infections are passed on.
A first episode of symptoms
At first you may feel generally unwell with a mild fever and aches and pains (flu-like symptoms). Groups of small, painful blisters then appear around your genitals and/or back passage (anus). They tend to erupt in crops over 1-2 weeks. The blisters soon burst and turn to shallow, sore ulcers.
Recurring episodes of symptoms
After the first episode, further episodes of symptoms occur in some people from time to time. This is called recurrent infection. It is not clear why the dormant virus erupts from time to time. Recurrences tend to be less severe and shorter than the first episode. It is more usual to have 7-10 days of symptoms with a recurrence, unlike the longer phase of symptoms that may occur during the first episode.
Most people do not develop a fever and do not feel particularly unwell during a recurrence. A tingling or itch in your genital area for 12-24 hours may indicate a recurrence is starting. The time period between recurrences is variable.
Recurrences tend to become less frequent over time. In people who have recurrences, their frequency can vary greatly. Some people have six or more a year. For others it is less frequent than this. On average, people tend to have 1 to 4 recurrences per year during the first two years after the first episode. Some people do not have recurrences at all after a first episode of symptoms.
Some people can identify some things that may trigger a recurrence. Such triggers include sunlight, physical illness, excess alcohol, or stress. If you can identify a trigger, it may be helpful to try to avoid this in the future, if possible.
What does genital herpes look like?
By Me, CC BY-SA 3.0, via Wikimedia Commons
No author listed, CC0, via Wikimedia Commons
The glands in your groin may swell and feel like lumps at the top of your legs. It is common to have pain when you pass urine, especially in women with genital herpes.
In women, a vaginal discharge may occur. Women may also have blisters and ulcers on the neck of the womb (cervix) at the top of the vagina. The inside of the back passage may also be affected. The ulcers and blisters can last up to 10-28 days and then gradually heal and go without scarring.
Sometimes less typical symptoms occur. For example, you may just have a small raw area, one or two small ulcers, or just an area of irritation with nothing to see. Sometimes symptoms last just a few days.
Note: sometimes a first episode of symptoms appears months or years after being first infected. This is why a first episode of symptoms can occur during a current faithful sexual relationship. You may have been infected months or years ago from a previous sexual partner who did not realise that they were infected.
It is not clear why some infected people develop symptoms, some don't and some have a first episode of symptoms months or years after first being infected. It may be something to do with the way the immune system reacts to the virus in different people.
How long does genital herpes last?
The symptoms of a first infection with genital herpes will usually last up to three or four weeks. The blisters appear in crops. After the symptoms go away the virus is still present in a nearby nerve, but is no longer active. This is sometimes called being dormant. It is usual to have repeated outbreaks of genital herpes symptoms over time. The recurrence symptoms usually last around 6-12 days.
How do you get genital herpes?
61%
of people would be worried about contracting genital herpes from a casual sexual encounter.
Source: Patient Sexual Health Survey
Genital herpes is an infection of the genitals (penis in men, vulva and vagina in women) and surrounding area of skin. It is caused by the herpes simplex virus. The buttocks and anus may also be affected. There are two types of herpes simplex virus:
- Type 1 herpes simplex virus is the usual cause of cold sores around the mouth. It also causes around half of cases of genital herpes.
- Type 2 herpes simplex virus usually only causes genital herpes. It can sometimes cause cold sores.
Genital herpes is usually passed on by skin-to-skin contact with the affected area of someone who is already infected with the virus. The moist skin that lines the mouth, genitals and back passage (anus) is the most susceptible to infection. This means that the virus is most commonly passed on by having vaginal, anal or oral sex, or just close genital contact with an infected person. For example, if you have a cold sore around your mouth, by having oral sex, you may pass on the virus that causes genital herpes.
Herpes simplex virus can also enter through a cut or break in the ordinary skin on other parts of the body. In this way the virus can sometimes affect fingers, hands, knees, etc, if they are in contact with another person's infected area. It is called a whitlow when it is on the fingers.
You are not likely to re-infect yourself with your own virus through accidental touching, or to catch back your own virus from an infected partner, on a different part of your own body.
Who should I see if I think I have genital herpes?
If you suspect that you have genital herpes or any other STI then see your GP or contact your local genitourinary medicine (GUM) clinic. You can go to the local GUM clinic without a referral from your GP. You can look for a GUM clinic near you in the UK by searching the 'Find a sexual health clinic service' - see Further Reading below. Your GP would also be able to advise you where your nearest clinic is.
Genital herpes test
A blister can be swabbed by a doctor or nurse to obtain a small sample to send to the laboratory. This can confirm the infection is due to the herpes simplex virus. It may also find out which type of herpes virus has caused the infection. Tests to look for other STIs may also be done at the same time.
These swab tests are best carried out in a GUM clinic. Your GP may sometimes do the tests but will normally advise you to attend a GUM clinic as soon as possible. You can make an appointment at most GUM clinics yourself without needing a referral from your GP. Sometimes a blood test is done as well but these are not very reliable. This determines whether you have had a herpes infection in the past, or whether this is the first time. It can also tell which type of herpes simplex virus it is.
Genital herpes treatment
General measures that may help to ease symptoms when they occur
- Painkillers such as paracetamol may help to ease pain.
- If it is painful when you pass urine, it is often less painful if you pass urine whilst sitting in a warm bath or shower (with water flowing over the area).
- A numbing (anaesthetic) ointment that you can buy at pharmacies, called lidocaine 5% gel, may relieve itching or pain. Some people also apply ointment about five minutes before passing urine if this is painful. Note: some people are sensitive (allergic) to anaesthetic ointments, and the ointment then makes skin symptoms worse. Applying Vaseline® before passing urine may be a helpful alternative to anaesthetic ointment.
- Ice wrapped in a tea towel (an ice pack) placed over the sores for 5-10 minutes may be soothing. Do not put ice directly on to skin, as this may cause an 'ice burn'.
- Have plenty to drink. This can help to make your urine less strong and less concentrated. This may make passing urine less painful.
- Do not use scented soaps, bubble bath, etc, as these may irritate the skin. Gentle cleaning of the open sores with just cotton wool and plain or salt water is best. Gentle drying with a hairdryer on its lowest setting may be more comfortable than with a towel.
- When you resume sexual activity after an episode has cleared, a lubricant may help, as some people find the friction of having sex may trigger a recurrence.
Other points:
- You should avoid having sex until the sores and blisters have cleared and/or you have seen a doctor for follow-up.
- It is best to be honest and tell your sexual partner if you have been diagnosed with genital herpes. If they have not got the infection, the doctor or nurse at the GUM clinic will explain ways to reduce the chances of passing it on to them. The doctor or nurse will also help explain that because of the way the virus works, it is not possible to tell how long ago you acquired the infection. Sometimes people are scared to tell their partners in case their partner thinks they have been unfaithful. Or it may be that they are worried their partner has been unfaithful and given them the infection. But because there is often a long time lag, this is often not the case. Your GUM clinic doctor or nurse will help you with these worries.
Genital herpes cannot be cured. The symptoms are improved by taking the antiviral medicines but medicine cannot clear the virus from your body for ever.
Antiviral medication
There are three antiviral medicines that are currently usually used to treat genital herpes:
They all come in different brand names. They work by stopping the herpes virus from multiplying. If an antiviral medicine is started early in an episode of symptoms, it tends to reduce the severity and duration of symptoms during an episode of genital herpes.
It is thought that these medicines all work as well as each other when used to treat genital herpes.
Antiviral medication for a first episode of genital herpes
An antiviral medicine is commonly prescribed for a first episode of genital herpes. (A first episode of genital herpes is also called a primary episode.) A five-day course of treatment is usual but this may be extended by a few days if blisters are still forming. With a first episode of genital herpes, the sores and blisters may last from about 10 days up to 28 days. This is usually much reduced if you start an antiviral medicine within five days of the onset of symptoms. The earlier the medicine is started, the better the chance of easing symptoms.
Antiviral medication for recurrent episodes of genital herpes
Further episodes of symptoms (recurrences) tend to be milder and usually last just a few days. You usually have 7-10 days of symptoms rather than 10-28 days that can occur with a first episode. Antiviral medication is often not needed for recurrences. Painkillers, salt baths, and local anaesthetic ointment (such as lidocaine) for a few days may be sufficient to ease symptoms. However, an antiviral medicine may be advised for recurrent episodes of genital herpes in the following situations:
If you have severe recurrences
If you take a course of an antiviral medicine as soon as symptoms start, it may reduce the duration and severity of symptoms. You may be prescribed a supply of medication to have ready at home to start as soon as symptoms begin. This kind of 'as needed' treatment tends to be prescribed if you are having severe attacks of genital herpes fewer than six times a year. There are a number of different options of courses of treatment to take, ranging from one to six days in length, and with different daily regimes.
If you have frequent recurrences
You may be advised to take an antiviral medicine every day. In most people who take medication every day, the recurrences are either stopped completely, or their frequency and severity are greatly reduced. A lower maintenance dose rather than the full treatment dose is usually prescribed. A typical plan is to take a 6- to 12-month course of treatment. You can then stop the medication to see if recurrences have become less frequent. This type of continuous treatment can be repeated if necessary. This type of daily treatment tends to be prescribed if you have severe attacks of genital herpes more than six times per year.
For special events
A course of medication may help to prevent a recurrence during special times. This may be an option even if you do not have frequent recurrences but want to have the least risk of a recurrence - for example, during a holiday or during exams.
Are there any side-effects from antiviral medicines?
Most people who take antiviral medication get no side-effects, or only minor ones. Feeling sick (nausea), being sick (vomiting), diarrhoea, and tummy (abdominal) pain, as well as skin rashes (including photosensitivity and itching) are the most common side-effects.
Read the leaflet inside the medication packet for a full list of possible side-effects.
Can genital herpes be cured?
Genital herpes cannot be cured. The symptoms are improved by taking the antiviral medicines but medicine cannot clear the virus from your body for ever.
Genital herpes in pregnancy
A specialist will normally advise about what to do if you develop genital herpes whilst you are pregnant, or if you have recurrent genital herpes and become pregnant. This is because there may be a chance of passing on the infection to your baby.
A first episode of genital herpes whilst you are pregnant
If you develop a first episode of genital herpes within the final six weeks of your pregnancy, or around the time of the birth, the risk of passing on the virus to your baby is highest. In this situation there is about a 4 in 10 chance of the baby developing a herpes infection. The baby may develop a very serious herpes infection if he or she is born by a vaginal delivery.
Therefore, in this situation your specialist may recommend that you have a caesarean section delivery. This will greatly reduce the chance of the baby coming into contact with the virus (mainly in the blisters and sores around your genitals). Infection of the baby is then usually (but not always) prevented.
However, if you decide against a caesarean section and choose to opt for a vaginal birth, the specialist is likely to recommend that you be given antiviral medication (usually aciclovir). This is given into your veins (intravenously) during your labour and birth. They may also suggest that antiviral medication be given to your baby after he or she is born.
As long as there are two months between you catching the virus and giving birth to your baby, a normal vaginal delivery is likely to be safe for the baby. This is because there will be time for your body to produce protective proteins called antibodies. These will be passed on to the baby through your bloodstream to protect it when it is being born.
The specialist may advise that you should be treated with antiviral medication at the time of infection. This helps the sores to clear quickly. In addition, your doctor may advise that you should take antiviral medication in the last four weeks of pregnancy to help prevent a recurrence of herpes at the time of childbirth. Antiviral medicines such as aciclovir have not been found to be harmful to the baby when taken during pregnancy.
If you have recurrent genital herpes and become pregnant
If you have recurring episodes of genital herpes, the risk to your baby is low. Even if you have an episode of blisters or sores during childbirth, the risk of your baby developing a serious herpes infection is low. This is because you pass on some antibodies and immunity to the baby during the final two months of pregnancy.
For most women with recurrent genital herpes, it is felt to be safe to have a normal vaginal delivery. This is even the case if you have a recurrence whilst giving birth. However, you and your specialist will weigh up the pros and cons of vaginal delivery vs caesarean section. If you do have a recurrent episode when you go into labour, you should discuss your options with your specialist and together decide the best way that your baby should be delivered.
Often antiviral medication will be advised in the last four weeks running up to childbirth. This may help to prevent a recurrence of blisters during childbirth. Again, your specialist will be able to advise on the pros and cons.
In summary
A first episode of herpes around the time of birth can be serious for the baby and a caesarean section is usually advised. In any other situation - an earlier primary infection or a history of recurrent episodes - the risk to the baby is low and your specialist will advise on possible options. This may include taking antiviral medication, as well as the type of delivery method.
How can genital herpes be prevented?
There is not yet a vaccine to protect against the herpes virus and therefore prevent genital herpes. There are a number of things to consider which may reduce your risks of getting genital herpes or of passing it on to others. These include:
- Consider the use of condoms always, even in established relationships. This is because a person can carry the herpes virus for a very long time and pass it on without ever being aware of it. Condoms do not completely protect against herpes but they reduce the risk.
- The more sexual partners you have, the more the risk of picking up any STI, including herpes. So avoiding having a large number of partners will cut down your risk.
- Avoid having sex with somebody with an active genital herpes infection (ie somebody with visible genital sores or blisters).
- Also avoid intimate contact with a person who has a cold sore.
- If you have an active herpes infection yourself, avoid having sex with anyone else in order to prevent passing it on.
- If one partner finds out they have herpes, it is wise to tell the other. This can reduce transmission rates.
- If a person knows they have recurrent herpes, taking a regular antiviral medicine can reduce the risk of passing on the virus.
- In particular, a pregnant woman should avoid having sex with somebody with active herpes, because of the extra risk to the baby during delivery
Should I have sex if I have genital herpes?
When you have symptoms (during a primary episode or recurrence)
Herpes simplex virus is very contagious when blisters are present. There is a high chance of passing on the virus if you have sex. You should not have sex from the time symptoms first start until they are fully over. If you do have sex, using a condom may not fully protect against passing on the virus, as the condom only protects the area that is covered.
When you do not have symptoms (which is most of the time)
It is less likely that you will pass the virus on when you have sex. However, some virus will be present on the genital skin surface from time to time, although infrequently. So, there is still a small chance that you may pass on the virus when you have sex when you do not have symptoms. It is best to discuss things with your sexual partner. Using a condom each time you have sex is thought to reduce the chance further. However, using a condom cannot completely stop the chance of passing on the virus.
Taking antiviral medication long-term to prevent recurrences (suppressive treatment) also reduces the risk of passing on the virus. However, very few people need to take this treatment all the time.
Note: if your sexual partner already has the same virus then you cannot re-infect each other. Your partner may be infected but may not have symptoms. It may be helpful to discuss things with a doctor or nurse at a GUM clinic.
Further reading and references
Herpes simplex - genital; NICE CKS, January 2023 (UK access only)
Sexually transmitted infections (STIs): surveillance, data, screening and management; UK Health Security Agency (Last updated February 2020)
Patel R, Kennedy OJ, Clarke E, et al; 2017 European guidelines for the management of genital herpes. Int J STD AIDS. 2017 Dec28(14):1366-1379. doi: 10.1177/0956462417727194. Epub 2017 Aug 24.
Management of Genital Herpes in Pregnancy; British Association of Sexual Health and HIV and Royal College of Obstetricians and Gynaecologists (Oct 2014)
Find a sexual health clinic near you; NHS services