Herpes simplex is part of a wider group of herpes viruses. All of us have experience with these viruses. Most of us have had chickenpox (herpes zoster). Chickenpox can recur as shingles when you get older. At least 25% of us have cytomegalovirus (HH-5). Nearly all of us are positive for Epstein Barr (HH-4) antibodies. And, most of us have herpes simplex 1 or 2, or both. Even if you’ve not had symptomatic herpes simplex infection, well over 80% of the adult population in many countries has the virus.

More people have been infected with herpes than those who have not. It happens to lots of people, some of us with symptoms and some without. The key thing is not whether you are infected or not, but whether it is causing symptoms or not – and if it is, then what can be done about it.

Genital herpes is a common viral infection caused by the herpes simplex virus (HSV). There are two types of the virus, types 1 and 2 (HSV-1 and HSV-2). As well as genital herpes, HSV can infect the face and cause cold sores. HSV-1 and HSV-2 lesions look the same and can only be distinguished by a specific swab and subsequent laboratory testing.

What is a virus?

Understanding viruses and how they work is the key to understanding genital herpes.

A virus is a very primitive form of life. As an intracellular parasite, a virus cannot live by itself and is entirely dependent on the cellular machinery of the cells it invades. Viruses and bacteria are the microbial organisms that most commonly cause infection in humans, but bacteria are larger and have their own cellular machinery which enables them to live free of cells and makes them easier to isolate and eliminate.

The herpes virus

Viral shedding

The initial infection that causes symptoms is usually most severe as the body’s immune system has not yet come into contact with the virus.

An initial infection lasts around 14-21 days (without antivirals, which would shorten the outbreak) and it’s not uncommon for someone to experience a range of generalised symptoms, such as fever, aches and pains, as well as specific genital symptoms. For others, an initial infection can be mild with minimal symptoms and often is unrecognised and undiagnosed.

The majority of people who acquire genital herpes will not experience any symptoms. Of those who do experience symptoms (20%), the first indication of infection usually starts between 2–20 days after exposure to the virus for some it may take months or even years. This is referred to as the first, initial or primary episode. The development of symptoms may take longer or be less severe in some people, especially those who have developed antibodies to HSV-1 from a previous cold sore infection.

Symptoms can start with tingling, itching, burning or pain (these are warning symptoms also known as the ‘prodrome’) followed by the appearance of painful red spots which, within a day or two, evolve through a phase of clear fluid-filled blisters which rapidly turn whitish-yellow. The blisters burst, leaving painful ulcers which dry, scab over and heal in approximately 10 days.

Sometimes the development of new blisters at the early ulcer stage can prolong the episode. On the other hand, the blister stage may be missed completely and ulcers may appear like cuts or cracks in the skin. People with vulvas may also notice vaginal discharge.

The severity and range of symptoms differ from person to person. People with vulvas frequently experience painful urination, and when this happens, it’s important to avoid the problem of urinary retention by drinking plenty of fluids to dilute the urine and thereby reduce pain and stinging. Sitting in a partially filled bath when urinating also helps. People can experience generalised fever, aches and pains, and a depressed run-down feeling.

Genital herpes can be elusive

The genital sites that are common for herpes sores are the vulva, the cervix and the shaft, glans (end of the penis), foreskin and base of the penis. Sometimes if herpes is on the inside of the genitalia people can get a discharge from their urethra or vagina. Herpes can also infect the skin around the anus and buttocks. If herpes is active inside the anal canal this can cause pain. Other sites where herpes sores can be present is the scrotum or the mons pubis (the triangle of skin where pubic hair grows).

Some people do not experience symptomatic recurrences, but for those who do, recurrences are usually shorter and less severe than the primary episode. Recurrences may be preceded by warning symptoms (also known as prodromal symptoms) such as tingling, itching, burning or pain.

As with the initial episode, there is a large variation in people’s experience of recurrences. Approximately 80% of people who have a first episode caused by HSV-2 will have at least one recurrence. The recurrence rate for genital HSV-1 infections is considerably lower, estimated to be around 10-20%. Genital herpes caused by HSV-2 recurs on average 4–6 times per year, and this will reduce with time. While HSV-1 infection occurs less often, some people having only one outbreak or no recurrences after the initial episode. A minority will have more frequent recurrences.

What triggers a recurrence of genital herpes?

A recurrence takes place when HSV reactivates in the nerve ganglion at the base of the spinal cord and particles of virus travel along the nerve to the site of the original infection in the skin or mucous membranes (e.g. the moist skin lining the inside of the genitals, mouth, anus and urethra). Sometimes, the virus travels down a different nerve causing recurrent symptoms at another site such as the buttocks or thighs.

Although it is not known exactly why the virus reactivates at various times it is likely that triggers maybe individual; the cause can be separated into the physical and the psychological.

• Physical:
  • Hormonal: Menstrual cycle, the hormonal fluctuations during menstruation can trigger a herpes episode in some individuals. Changes in oestrogen and progesterone levels may affect the immune response or cause localised inflammation, which can contribute to an outbreak.
  • Immunological: Being run-down - Physical exhaustion or general fatigue can weaken the immune system, making it easier for the herpes virus to reactivate. Any illness or condition that suppresses the immune system, such as HIV, certain medications, or chronic diseases, can trigger a herpes recurrence. Drinking alcohol - Excessive alcohol consumption can suppress the immune system, reducing the body's ability to keep the virus dormant, potentially leading to an outbreak.
  • Local skin trauma: Another genital infection - A concurrent genital infection can compromise the skin barrier, making it easier for the herpes virus to reactivate. Friction or damage to the skin - Activities such as sexual intercourse, particularly without proper lubrication, can cause irritation or microtrauma to the genital skin. Exposure to strong sunlight - Sunburn or excessive UV exposure can damage skin cells and may cause a recurrence.
• Psychological: Recent studies have demonstrated that periods of prolonged stress or depression may precipitate more frequent recurrences. It is also common to experience stress and anxiety from having recurrences.

You can get genital herpes by having sexual contact (vaginal, oral or anal sex) with someone who carries HSV. It used to be believed that transmission (passing it on) only occurred if herpes blisters or sores were present. However, it is now known that transmission can occur when herpes blisters or sores are not present. This can occur in three situations: