High-Risk Candidates for Complications of Chickenpox.

Elderly people. The older the patient, the higher the risk for complications from either chickenpox or shingles. Adults who smoke are at particularly higher risk for pneumonia from chickenpox.

Patients with Serious Illnesses. People with serious illnesses may be at risk for complications of the varicella-zoster virus. Patients with diseases, such as Hodgkin's disease, who receive bone marrow or stem cell transplants are at higher risk for herpes zoster and its complications.

Pregnant Women. Pregnant women who become infected with the varicella-zoster virus, whether in the form of chickenpox or shingles, are at increased risk for serious pneumonia.

The risk for the infant is lower or higher depending on when the mother became infected.
Chickenpox in the mother during early pregnancy poses a slightly increased risk for birth defects in the infant.
The highest risk for birth defects is about 2%, which usually occurs if the mother has chickenpox between the 13th and 20th week. Even in such cases, birth defects may only result in minor skin abnormalities. More serious defects include a smaller than normal head, eye problems, low birth weight, and mental retardation.
If women develop chickenpox (not shingles) within 5 days before and 2 days after delivery, their newborns are at risk for life-threatening varicella.
Newborns and Infants. Chickenpox in newborns is a life-threatening condition. Although chickenpox can still be very dangerous in older infants, most are protected by antibodies in breast milk from mothers who have had chickenpox. Children under age 1 who develop chickenpox are at higher risk for childhood shingles. All infants should have as little exposure as possible to people with chickenpox.