Date: 2 سال قبل
Primary varicella-zoster virus infection causes varicella (chickenpox). Reactivation of latent virus (usually in adults) causes herpes zoster (shingles), manifesting as vesicular rash with a dermatomal distribution and acute neuritis.
Varicella-zoster virus is usually transmitted by droplets and replicates initially in the nasopharynx. In seronegative individuals, viremia and chickenpox ensue. Latency is established in dorsal root ganglia, and virus reactivation results in virion transport down sensory nerves.
As with herpes simplex virus, interferon and cellular and humoral immunity are important defenses. Reactivated virus can cause disseminated disease in immunocompromised individuals.
Varicella-zoster virus is highly contagious; about 95 percent of adults show serologic evidence of infection.