The facts about herpes simplex – patient information leaflet

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It is very common!

Herpes simplex is the medical name for the virus that causes cold sores, genital sores and whitlows on fingers or hands. It is common: in the UK, six out of ten people have probably caught cold sores somewhere on the body by the age of 25 – and the rate is even higher in other countries. About three quarters of the people who have it never have symptoms. It is seldom of any medical importance. Serious complications are rare and are usually restricted to people who catch the virus on the face.

How many types are there?
There are two types of cold sore virus: herpes simplex type 1 and herpes simplex type 2. They are almost identical (they share over 90% of DNA). Either type may cause spots or sores on any bit of skin. The most common affected sites are the lips/face (up to two thirds of adults), and the genitals (around ten per cent of adults in the UK, higher in the USA). There are other herpes viruses including the ones that cause chickenpox and glandular fever.

What is the difference between the types?
At one time nearly all facial cold sore infections were caused by type 1 virus and type 2 was responsible for most 'genital herpes' diagnoses. This is no longer the case. Modern sexual habits now often include oral sex so the two types have been swapping sites. Nowadays around half the people with genital symptoms diagnosed in clinics are found to have type 1 virus and half have type 2. There must also be people with facial cold sores of either type. The only practical difference is that each type has a ‘preferred’ site and is more likely to recur if caught on the place it prefers - type 1 prefers the face and type 2 the genitals.

How and where can you catch it?
You catch herpes simplex by direct skin contact, usually with friction, with the affected patch of skin of someone who has it already. This means kissing, sex and/or oral sex. Transmission is very likely if there are obvious spots or blisters, much less likely if there are no symptoms present. It is not caught off towels, sheets, cups, cutlery, baths, swimming pools or from blood.

It is easier for the virus to affect thin skin (mucous membranes - lips and genitals) where the skin is thinner. Usually 'normal' or 'dry' skin is too thick to allow easy entry. However if skin is cut or broken in some way the virus may be caught on other areas. People with eczema or sunburn for example, may catch the virus elsewhere. It is also fairly common for people to have finger infections (‘herpetic whitlows’) because there is often broken skin on the fingers - paper cuts, bitten nails, soreness caused by cleaning products etc.

Can I catch it again – or give it back to my partner? What if my partner already has cold sores?
Herpes simplex is one of those childhood diseases you usually only catch once (like chickenpox). If you and your partner have the same type of herpes simplex you will not reinfect each other – even on different parts of the body.

If you each have different types you could both catch the type you do not have - from each other. You could catch one type in one place and another type elsewhere, or both types in the same place. However, most people only catch one type.

If you do catch a second type it will be milder, so it is likely you will not even notice at the time - and perhaps may never realise it.

Will I get recurrences?
Around half of those diagnosed only have symptoms once. Others have (milder) recurrences from time to time. In most people these decline over time and may stop altogether. If you are one of the unlucky people who gets too many recurrences, we can suggest both drugs and self-help suggestions to control them.

How does the virus hide in the body?
After infecting the skin cells the virus establishes itself in the nerves serving that patch of skin. It travels along the nerves to the nearest nerve ganglion where in up to half of cases it sits and does nothing. If the virus decides to recur it usually travels back to the same bit of skin. Sometimes it chooses a different nerve and appears nearby. However the virus is stuck in the part of the body where you catch it. If you catch it on the face it cannot recur below the chin; if you catch it genitally it cannot recur above the bikini line. (Important note: sometimes people catch the virus on two different sites on the same occasion e.g. hands and genitals or face and genitals - it depends what they get up to. Once primary symptoms have healed you will not spread the virus to other sites.)

Treatment?
Your doctor may prescribe antiviral pills, but these are not essential. You will get better by yourself. Aspirin, paracetamol or ibuprofen can help with pain. Also you can apply an anaesthetic gel or ointment to the area to numb it: lignocaine 2% gel and 5 % ointment can be bought cheaply at some chemists. The HVA can suggest other self-help treatments: see website or phone helpline.

Whether you will get another outbreak does not depend on the treatment you get but on your own immune response.

How can I avoid passing on the virus?
Don’t rub your affected bit of skin against someone else when you have symptoms or think they may be on the way. Warning signs may be itching or aching in the affected area.

Condoms can prevent transmission if they are put on before there is any skin contact with the affected skin area, and as long as they come in between the relevant bits of skin. (Obviously!)

Remember that cold sores on the face may be caught from oral sex with someone who has caught the virus on the genitals and "genital herpes" may be caught through oral sex from someone with facial cold sores.

Sometimes there may be a small amount of virus on the skin without causing symptoms. This is often just before a noticeable recurrence starts. This ‘asymptomatic shedding’ will usually be infrequent – no more than 2% of the time – and may not be enough to infect a partner. It diminishes with time. It is more likely to happen in the first year and especially in the first four months after infection. People who have been diagnosed usually recognise the warning signs of a recurrence before anything is visible. This is the time to avoid sex/skin contact with the affected part.

Pregnancy and "www information"
Herpes simplex hardly ever affects babies although you could get the opposite impression from some internet sites and books. Generally it is safe to say that if you see any information about herpes simplex that is worrying or frightening, it is probably incorrect - contact us for clarification. We have a detailed leaflet on pregnancy and childbirth, another on transmission...

The trouble is that herpes simplex suffers from an unwarranted stigma. It is caught by most people somewhere and many of us do not even notice. It is polite to avoid deliberately infecting someone else but in the end it is only a cold sore and is usually trivial.

Small print
Information about recurrences and transmission of the virus to different sites on the body assumes that you have a normal immune system. People who have defective or suppressed immune systems may have extra problems with many infections including herpes simplex. In these cases doctors take extra steps to help them

The Herpes Viruses Association says "If you see an article or website about ‘herpes’ that is scary, it is probably wrong. Contact us for the facts.". See About us for contact details.

Patrons:
Professor Michael W Adler CBE MD FRCP FFCM
Dr B A Evans FRCP
Dr D J Timmins MB ChB FRCP MRCGP MFFP
Dr Elizabeth Claydon MRCP MB ChB
Dr David Barlow MA BM FRCP
Dr Miriam Stoppard MD FRCP
Dr David Bull MBBS BSc
Dr Phil Hammond MB BChir MRCGP