by Rick Alan
Chickenpox is a highly contagious viral infection. It produces a widespread itchy rash and crusting. The varicella zoster virus (VZV) causes chickenpox. The virus can spread from person to person via:
The virus is most contagious for 1-2 days before the rash erupts and during the first day or so after the rash has broken out. It remains contagious until all of the blisters have crusted.
Because of an extensive vaccination program, the incidence of chickenpox has declined greatly in the United States. The majority of cases (about 90%) occur in infants, children, and adolescents under age 14. The incidence among adults 20 or older is very low (approximately 5% of cases). When contracted during childhood, chickenpox is usually not serious. Serious complications are more common when contracted by adults (including adolescents), newborns, or people with a suppressed immune system. These complications can include:
American Academy of Family Physicians website. Available at: http://www.familydoctor.org/.
The Merck Manual of Medical Information. 17th ed. Simon and Schuster, Inc.; 2000.
Centers for Disease Control and Prevention website. Available at: http://www.cdc.gov.
Last reviewed October 2012 by Michael Woods, MD
Last Updated: 10/11/2012