Chickenpox is a viral infection in which a person develops very itchy blisters all over the body. It was more common in the past. The illness is rare today because of the chickenpox vaccine.
Alternative Names
Varicella; Chicken pox
Causes
Chickenpox is caused by the varicella-zoster virus. It is a member of the herpesvirus family. The same virus also causes shingles in adults.
Chickenpox can be spread very easily to others from 1 to 2 days before blisters appear until all the blisters have crusted over. You may get chickenpox:
- From touching the fluids from a chickenpox blister
- If someone with the disease coughs or sneezes near you
Most cases of chickenpox occur in children younger than age 10. The disease is most often mild, although serious complications may occur. Adults and older children get sicker than younger children in most cases.
Children whose mothers have had chickenpox or have received the chickenpox vaccine are not very likely to catch it before they are 1 year old. If they do catch chickenpox, they often have mild cases. This is because antibodies from their mothers' blood help protect them. Children under 1 year old whose mothers have not had chickenpox or the vaccine can get severe chickenpox.
Severe chickenpox symptoms are more common in children whose immune system does not work well.