Varicella, also called chickenpox, is a common, acute, and highly contagious infection caused by the herpesvirus varicella-zoster (V-Z), the same virus that, in its latent stage, causes herpes zoster (shingles). It can occur at any age, but it’s most common in 2- to 8-year-olds.

The varicella vaccine is effective in preventing varicella in up to 90% of recipients. The American Academy of Pediatrics recommends the vaccine for all children and for adolescents and adults who haven’t had varicella. It’s unknown how the vaccine affects shingles. (See Varicella vaccine, page 890.)


Congenital varicella may affect infants whose mothers had acute infections in their first or early second trimester. Neonatal infection is rare, probably due to transient maternal immunity. Second attacks are also rare.

Varicella is transmitted by direct contact (primarily with respiratory secretions; less often with skin lesions) and respiratory droplets. The incubation period lasts from 13 to 17 days. It’s probably communicable from 1 day before lesions erupt to 6 days after vesicles form (it’s most contagious in the early stages of eruption of skin lesions).

Most children recover completely, but potentially fatal complications may affect children receiving corticosteroids, antimetabolites, or other immunosuppressant agents, and those with leukemia,
other neoplasms, or immunodeficiency disorders. Congenital and adult varicella may also have severe effects.

Jun 16, 2016 | Posted by in GENERAL & FAMILY MEDICINE | Comments Off on Varicella

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