Le area is manifested by Rashes painful along a nerve or nerve ganglion. These eruptions occur as a result of the reactivation of the virus that causes chickenpox, the varicella zoster virus (VVZ). Shingles most often affects the thorax or face, but all parts of the body can be affected.

Sometimes the pain caused by shingles persists for months or even years after the rash heals: this pain is called neuralgia or postherpetic pain.

Causes

Following a varicella, almost all viruses are destroyed except a few. They remain dormant in the nerve ganglia for several years. With age or due to illness, the immune system may lose its ability to control virus, which can reactivate. A inflammatory reaction then settles in the ganglia and in the nerves, causing the appearance of vesicles arranged in clusters on the skin.

It may be that adults already infected who have been in contact with children with chickenpox benefit from a protected increased against shingles. Scientists believe that a second exposure to the virus stimulates the immune system and thus helps keep the virus dormant.

Who is affected?

About 90% of adults worldwide have had chickenpox. They are therefore carriers of the varicella zoster virus. About 20% of them will get shingles in their lifetime.

Evolution

Left untreated, lesions of the area last an average of 3 weeks. Most of the time, only one attack of shingles occurs. However, the virus may reactivate several times. This is what happens in the case of about 1% of those affected.

Possible complications

The pain sometimes persists after the skin lesions have healed: this is the post-shingles neuralgia (or postherpetic neuralgia). This pain is compared to that of sciatica. People who suffer from it say that they experience real “electric shocks”. The heat, the cold, the simple friction of a garment on the skin or the blast of the wind can become unbearable. The pain can last for weeks or months. Sometimes it never stops.

We try as much as possible to avoid this situation, which can become a considerable source of physical and psychological suffering : Neuralgic pain can be persistent, intense and difficult to treat effectively. Taking antiviral drugs from the onset of shingles would help prevent them (see the Medical treatments section).

The risk of post-herpes zoster neuralgia increases withage. Thus, according to a study carried out in Iceland among 421 people, 9% of people aged 60 and over experienced pain 3 months after a first attack of shingles, compared to 18% of people aged 70 and over¹².

Post-shingles neuralgia is thought to be caused by damage to nerve fibers, which start sending pain messages to the brain in a confused manner (see diagram).

Other types of complications can occur, but they are rare: eye problems (up to blindness), facial paralysis, non-bacterial meningitis or encephalitis.

Contagion

Le area does not spread from person to person. However, the liquid inside the red vesicles that form during a shingles attack contains several particles of the chickenpox virus. This liquid is therefore very contagious : A person who touches it can get chickenpox if they have never had it. To enter the body, the virus must come into contact with a mucous membrane. It can infect someone who rubs their eyes, mouth or nose, for example, with a contaminated hand.

Le hand washing helps prevent transmission of the virus. It is also advisable to avoid physical contact when the fluid is draining from the vesicles. People who have not had chickenpox and whose infection may have serious consequences must be extra careful: this is the case, for example, of pregnant women (the infection can be dangerous for the fetus), people whose weakened immune system and newborns.