Health Centres - Genital herpes
What is genital herpes?
Genital herpes is a contagious disease caused by the herpes simplex virus (HSV), which infects the skin and mucous membranes of the genitals and around the rectum. It is transmitted by physical and sexual contact.
Herpes appears as redness and small watery blisters on the genitals. It may be accompanied by pain, itching and burning. The blisters will burst and turn into small ulcers, which will heal after two to three weeks without scarring.
Herpes simplex virus
- There are two types of herpes simplex virus that both attack skin and mucous membranes in all areas of the body.
- HSV-1, the most common type, usually appears as cold sores on the mouth and lips.
- HSV-2 affects the genitals.
- Around 80 per cent of the adult population have antibodies in their blood indicating past infection with HSV-1 and 25 per cent have antibodies against HSV-2. Antibodies represent the 'memory' of the body's immune system, enabling it to recognise and then attack foreign material, such as viruses, when they re-enter the body. However, the presence of antibodies is no guarantee that further virus attack will be repelled efficiently or completely. Repeated attacks of herpes infection can and do therefore occur.
How does the herpes simplex virus affect the body?
HSV attacks the cells of the outer layer of skin and blisters will be formed. From the skin, HSV is transported through the bloodstream down to the nerve roots where the virus lies dormant.
If the skin is damaged in the area around the nerve where the HSV is located, or if the immune system is weakened, for example by a heavy cold or fatigue, the virus will be reactivated and will appear again as herpes.
How is genital herpes transmitted?
- Genital herpes is primarily a sexually transmitted disease.
- A cold sore can also infect the genitals through oral sex.
- The virus is still contagious and can be passed on even if there are no blisters or ulcers present.
- Pregnant woman with genital herpes should consult their doctor. Babies can be infected with herpes at birth because they can pick up the virus from the birth canal or vulva. This risk does not apply to a Caesarean section.
What are the symptoms of genital herpes?
The first eruption of herpes will appear four to seven days after the time of infection. The first sign is an uncomfortable prickly and piercing sensation. This will be followed after a couple of hours or up to two days later by small blisters on the skin. The blisters will turn into small ulcers in two to three weeks.
The first outbreak of genital herpes will cause the most noticeable symptoms. Some people will have very weak symptoms or none at all.

