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Understanding Cold Sores

Is it common to be infected with cold sores?

Two-thirds of the world's population under 50 years old have the highly infectious herpes virus, usually after catching it first in childhood, the World Health Organization says in its first estimate of global prevalence of the disease. Although there are many who carry the virus, only about 20 to 40 percent of people who have the virus develop cold sores. Some people have frequently recurring cold sores around two or three times a year, while others have one cold sore and never have another. Some people never get cold sores at all because the virus never becomes active.

What is a cold sore?

A cold sore is a group of tiny, painful, fluid-filled blisters on and around your lips. Cold sores are a common viral infection caused by the Herpes Simplex Virus (HSV). They are also known as fever blisters or herpes simplex labialis.

Why do some of us not show symptoms of cold sores?

Most cold sores are caused by a virus called the Type 1 strain (HSV-1). Although a first cold sore usually occurs in childhood, the first infection can cause no symptoms.The virus infects through the moist inner skin that lines the mouth. After the first infection, the virus settles in a nearby nerve sheath and remains there for the rest of your life. For most of the time, the virus lies dormant (inactive) and causes no symptoms. However, in some people the virus becomes active from time to time. When activated, the virus multiplies and travels down the nerve sheath to cause cold sore blisters around the mouth. Some people have cold sores often, others only now and then.

How do I know if it is the cold sore?

Symptoms of cold sores usually happen in stages.

Stages of cold sores:

You may have a tingling, burning or itching feeling in the beginning before the blisters appear, which is usually found around your lips and nose.This can last several hours, or up to a day or so.
After the tingle, about 12 to 24 hours later, blisters form. One or more blisters appear which are usually sore. The blisters contain fluid that is full of the herpes virus. The area becomes red, swollen, and painful.
The blisters break open, and fluid comes out. This usually lasts 2 or 3 days. Cold sores are most contagious when you have oozing blisters (before forming hard scabs) because the virus easily spreads through contact with infected body fluids. But you can spread the virus even if you don't have blisters. Before the cold sores form hard scabs.
It might take several days for the cold sores to form scabs. When the scab forms on the sore, it might crack or bleed.
It will slowly get better and disappear when the scab falls off, leaving no scar. The blisters can take two to three weeks to heal completely. After recovery, some virus will remain dormant (inactive) in the nerve sheath, ready to cause another cold sore sometime in the future. Recurrences typically appear at the same spot each time and tend to be less severe than the first outbreak.

Other common symptoms associated with a cold sore attack:

Red or swollen gums
Swollen glands in your neck
Fever
Muscle aches.

Symptoms for first-time infections are more severe, symptoms may include:

Painful gums
Sore throat
Pain when swallowing
Headache
Upset stomach
Fever
Swollen lymph nodes

How do people catch the Herpes virus?

Let’s check out the modes of transmissions of the virus!

The herpes simplex virus type 1 (HSV-1) is commonly spread from person to person by close contact, such as kissing. Cold sores are contagious even if you don't see the sores. It is commonly passed on by skin contact such as kisses from a family member who has a cold sore. Cold sores are most contagious when you have watery blisters because the virus easily spreads through contact with infected body fluids.

What can I do if I have cold sores?

Avoid touching the cold sores -this can prevent the virus from spreading to other parts of the body which may cause serious complications.Only touch cold sores when applying topical creams. Creams, gels and other topical treatments should be dabbed on the cold sores rather than rubbed in. This is to minimise damage to the blisters which may spread the virus around, or cause more pain by breaking the blisters or scabs.
Antiviral creams - Aciclovir (Zovirax®) can be bought over-the-counter (OTC) at pharmacies. This does not kill the virus but prevents the virus from multiplying. It is more effective to use antiviral creams before the blisters form, then the cold sore may not last as long as usual and may be less severe. It has little effect on existing blisters but may prevent them from becoming worse. The cream may provide some protection against cold sores caused by sunlight if it is used before exposure.
Maintain cleanliness - Wash your hands thoroughly with soap and water after touching cold sores and after applying creams to them.
Use of lip balm if necessary - If you find that sunlight triggers your cold sores, try using sunscreen lip balm (SPF 15 or more) before going out into bright sunlight. Do not share lip balms with other people if you have cold sores.
Optional pain control - Pain can be eased by painkillers such as paracetamol or ibuprofen. Alternatively, painkilling gel such as Choline salicylate gel is available for pain control but cannot be used under the age of 16 due to the risk of Reyes’s syndrome. Lidocaine is also a local anaesthetic gel that can also be used to control pain.
Laser treatment - Some people have found that treatment with a type of laser beam called narrow-band light has worked well. This type of treatment is sometimes called photodynamic therapy which involves a machine that delivers narrow-band light.
Antiviral tablets - Aciclovir is also available in tablet form.There are other oral antiviral medicines too, such as valaciclovir. Oral antiviral tablets are not routinely used for the treatment of cold sores. Oral antiviral tablets may be prescribed in severe cold sore infections, in newborn babies, or in people who have a poor immune system (immunocompromised people). Severe viral infections such as a severe herpes infection can be extremely dangerous to the health of immunocompromised people.

What triggers an outbreak of cold sores?

Although it is not clear what causes the dormant virus to become active, some things that may trigger the virus to activate and cause a cold sore include:

Fever/Illness - Cold sores may occur during feverish illnesses such as colds, coughs and flu.
Menstruation - Cold sores are common around the time of monthly periods.
Stress - Being emotionally unstable may be a triggering factor towards cold sores.
Sunshine - Strong, direct sunlight may trigger cold sores in some people.

Is cold sores life threatening? When should I see a doctor/GP?

Usually you would not need to see a doctor if you have cold sores. Cold sores generally clear up without treatment. However, you are highly encouraged to see a doctor if:

You have a weakened immune system
The cold sores don't heal within two weeks
Symptoms are severe
You have frequent recurrences of cold sores
You experience irritation in your eyes

Aside from the aforementioned concerns, cold sores might also lead to other complications when the virus is spread to other areas of the body, you should see a doctor immediately when this happens.

Cold sores complications affecting other areas include:

Fingertips - Both HSV-1 and HSV-2 can be spread to the fingers. This type of infection is often referred to as herpes whitlow. Children who suck their thumbs may transfer the infection from their mouths to their thumbs.
Eyes - The virus can sometimes cause eye infections. Repeated infections can cause scarring and injury, which may lead to vision problems or loss of vision.
Widespread areas of the skin - People who have a skin condition called atopic dermatitis (eczema) are at higher risk of cold sores spreading all across their bodies and a painful rash covers large areas of skin. This can become a medical emergency.
Brain or spinal cord - The virus can cause dangerous inflammation called meningitis or encephalitis, especially in people who have weakened immune systems.

What should we AVOID to prevent the spread of virus?

When you have a cold sore you should not kiss anyone or allow anyone to come into skin contact with the sore. In particular, avoid kissing newborn babies and anyone who has a poor immune system (an immunocompromised person). Immunocompromised people include people having chemotherapy for cancer and people with conditions such as AIDS.
Try not to touch or pick cold sores.
There is a risk of infecting the eyes with the cold sore virus if your contact lenses become contaminated. You can prevent this with careful handwashing before handling your contact lenses. If you have disposable lenses and you suspect you have contaminated them, it is probably best to throw them away.

Why are some people more at risk of cold sores?

Almost everyone is at risk of cold sores. Most adults carry the virus that causes cold sores, many people who are infected with the virus that causes cold sores never develop signs and symptoms.

You're most at risk of complications from the virus if you have a weakened immune system from conditions and treatments such as:

HIV/AIDS
Atopic dermatitis (eczema)
Cancer chemotherapy
Anti-rejection drugs for organ transplants

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