
Chickenpox is a highly contagious illness that is common in children. It causes an itching skin rash with blisters. The disease is caused by the varicella-zoster virus and usually runs its course without problems.
The viral infection is transferred from one person to another through direct contact with the broken chickenpox blisters and through airborne droplets.
The infectious period lasts from about three days before the rash appears until all the blisters have formed scabs.
The incubation period between being infected with chickenpox until the disease breaks out and symptoms appear is 10 to 20 days.
Shingles can affect adults and children, but is much more common in older people. It can not be triggered by contact with someone who has chickenpox. Shingles is contagious and may itself cause chickenpox. However, contact with a person with shingles or chickenpox cannot cause shingles.
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