Varicella

Chickenpox is caused by Varicella zoster virus and is usually mild, but it may be severe in infants, adults and persons with impaired immune systems. Almost everyone gets chickenpox by adulthood (more than 95% of Americans). Chickenpox is highly contagious. CDC estimates that 4 million cases occur each year. For more detail and original CDC source click here:

http://www.cdc.gov/od/oc/media/fact/chickenp.htm.

Varicella
Child with mild Chicken Pox	Child with severe Chicken Pox