Varicella-zoster virus (VZV) can establish lifelong persistent infections and cause severe diseases in humans of all ages. The virus can be spread from person to person by direct contact, inhalation of aerosols from vesicular fluid of skin lesions of acute varicella or zoster, and possibly through infected respiratory secretions that also may be aerosolized.
Primary infection leads to acute varicella or “chickenpox”, usually from exposure either through direct contact with a skin lesion or through airborne spread from respiratory droplets. After the primary infection, VZV stays in the body (in the sensory nerve ganglia) as a latent infection. Varicella is characterized by a pruritic, maculopapular, vesicular rash that evolves into noninfectious dried crusts over a 3- to 7-day period.
Reactivation of latent infection causes herpes zoster (shingles). Shingles is not caused by the same virus that causes genital herpes, a sexually transmitted disease. Shingles cannot be passed from one person to another. However, the virus that causes shingles, the varicella zoster virus, can be spread from a person with active shingles to another person who has never had chickenpox.
VZV enters the host through the respiratory tract and conjunctiva. It replicates at the site of entry in the nasopharynx and in regional lymph nodes. A primary viremia occurs 4 to 6 days after infection and disseminates the virus to other organs, such as the liver, spleen, and sensory ganglia.
Varicella-zoster virus
