What is chickenpox?

What is chickenpox?

Chickenpox is an infection that causes a skin rash. The disease is caused by a germ called varicella-zoster virus. (Chickenpox itself is also called varicella-zoster.) Most people will get the virus when they’re young if they haven’t had a chickenpox vaccine.

A child with chickenpox can easily give the virus to other children. Chickenpox today is much less common because most children are vaccinated when they are young. Before the first vaccine against chickenpox was approved in the U.S. in 1995, almost everyone got chickenpox. Very few had complications.

Once you’ve had chickenpox, you won’t catch it again from another person. If you’re not vaccinated, you can get chickenpox at any age. Adults who get chickenpox may become very sick, so it's better to have chickenpox when you're a child, or prevent getting it by being vaccinated.