What Causes Varicella Zoster Virus (VZV) Infection?
Chickenpox and zone are caused by the same virus, the VZ virus (like the initials of the 2 diseases, or VZV). After the primary infection (chickenpox), the virus persists in the body indefinitely in an inactive (quiescent) form. Sometimes, in adulthood, this virus reactivates, and causes a localized infection: the zone.
How is shingles transmitted?
The zone does not catch. It follows chickenpox most often caught in childhood. The virus remains silent for years, harbored in the nerve ganglia around the spine. Sometimes, on the occasion of triggering circumstances, there is a virus reactivationwhich migrates in the nerve fibers sensory cells to form vesicles in the nervous territory concerned. The crisis of zone is favored by age (after 65), the decline in immune defenses (anti-cancer treatment, HIV, corticosteroids, etc.), sometimes a state of fatigue or anxiety.
What are the symptoms of shingles?
The zone manifests itself in a well localized, unilateral nervous territory. It begins with a burning sensation localized, painful, often between the ribs (zona intercostal). After a few days appear in the painful area small vesicles filled with an often cloudy liquid, identical to those of chickenpox. These “blisters dry up and eventually fall off in 4 to 8 days. There may be several successive pushes. THE zone heals spontaneously without sequelae, but there may be, especially in the elderly, residual pain, called postherpetic neuralgia.
When shingles reaches certain critical nerve territories, complications are possible:
The ophthalmic shingles encompasses the eye. We then observe the burning sensation and the eruption around one eye, on the forehead. There can be severe consequences for the eye.
Facial nerve damage can cause facial paralysis unilateral with pain in the ears and blisters in the ear. Dizziness is common.
When to measure immunity against shingles in the laboratory?
There is no diagnosis or biological test for the zone. It is a clinical diagnosis.
Is there a treatment for shingles?
And zone simple is treated simply by avoiding the bacterial superinfection vesicles (disinfection of the skin), and in case of pain, analgesics adapted to the intensity of the pain. Oral antivirals (valaciclovir or famciclovir) are effective if administered very early (no later than 3 days after the appearance of skin manifestations).
In case of serious area (ophthalmic shinglesor at the immunocompromised person), oral antiviral treatment is systematic.
Postherpetic pain is difficult to treat, and analgesics or contact anesthetics are used.
Vaccination against zone is recommended for people over 65, including people who have already had a zone. This vaccination aims above all to prevent post-herpetic pain.