What is disseminated varicella?

Varicella-zoster is the virus that causes varicella (chicken pox), herpes zoster (shingles), and rarely, severe disseminated disease including diffuse rash, encephalitis, hepatitis, and pneumonitis. Disseminated disease is most often seen in immunocompromised patients.

What does it mean to test positive for varicella zoster?

A positive VZV IgG result indicates the presence of antibodies to varicella zoster virus. The test cannot distinguish between past infection and current infection though, so a positive result could indicate active infection and not immunity.

Can varicella be reactivated?

The varicella zoster virus (VZV) is 1 of 8 herpes viruses that infect humans. Like the others, it establishes a latent infection that can reactivate in the body.

Is varicella and chickenpox the same?

Varicella (chickenpox) is an acute infectious disease. It is caused by varicella-zoster virus (VZV), which is a DNA virus that is a member of the herpesvirus group. After the primary infection, VZV stays in the body (in the sensory nerve ganglia) as a latent infection. Primary infection with VZV causes varicella.

What causes reactivation of varicella-zoster virus?

Primary infection causes varicella (chickenpox), after which virus becomes latent in ganglionic neurons along the entire neuraxis. With advancing age or immunosuppression, cell-mediated immunity to VZV declines and virus reactivates to cause zoster (shingles), which can occur anywhere on the body.

Where in the body does the varicella-zoster virus lie dormant?

After the primary infection (chickenpox), the virus lies dormant in the nerves, including the cranial nerve ganglia, dorsal root ganglia, and autonomic ganglia. Many years after the person has recovered from chickenpox, VZV can reactivate to cause neurological conditions.

How do I know if I am immune to varicella?

If testing is done to see if you are at risk of developing an infection and it finds varicella-related immunoglobulin G (IgG) antibodies in your blood, it means you are immune. You have had a chickenpox infection or have been immunized successfully.

How does varicella get reactivated?

Shingles occurs when the varicella-zoster virus is reactivated due to a weakened immune system. This can create a painful, blistering rash. The risk of getting shingles goes up with age, with increased likelihood after age 50.

What reactivates varicella?

What can chickenpox be mistaken for?

Vesiculopapular diseases that mimic chickenpox include disseminated herpes simplex virus infection, and enterovirus disease. Dermatomal vesicular disease can be caused by herpes simplex virus and can be recurrent.

Do adults need a varicella booster?

All adults without evidence of immunity to varicella (as defined below) should receive 2 doses of single-antigen varicella vaccine or a second dose if they have received only 1 dose.