Expert Advice

When Is Chickenpox Contagious?

Pediatrics Expert Advice from Henry Bernstein, M.D.

Q
When is chickenpox contagious? Is it dangerous for a six-month-old baby to get them? Can you tell me where to get more information?
A
Chickenpox is a virus that is easily spread from one person to another through the air. When a person develops chickenpox, they are considered contagious -- able to spread the disease to someone who hasn't had it -- for 24 hours prior to the rash first appearing and then for as many days as it takes for the rash to crust over (often times up to an entire week). If someone who has never had chickenpox is exposed to someone with it, you have to wait 10 to 21 days to know whether or not they are going to get it.

Children of all ages can get chickenpox. The older you are when you get it, the greater the likelihood that any of the potential complications may occur. In general, a normally healthy six-month-old baby with chicken pox does better than an adult. In fact, if the baby's mother has already had chickenpox, her antibodies (things in the blood that help protect against it) were passed to the baby during birth. This then helps the infant and makes the disease milder.

Hope this answers your question. If you need more information on chickenpox you can ask your pediatrician.

Henry Bernstein, M.D., is currently the associate chief of the Division of General Pediatrics and director of Primary Care at Children's Hospital, Boston. He also has an academic appointment at Harvard Medical School.

Please note: This "Expert Advice" area of FamilyEducation.com should be used for general information purposes only. Advice given here is not intended to provide a basis for action in particular circumstances without consideration by a competent professional. Before using this Expert Advice area, please review our General and Medical Disclaimers.