Health A-Z
Chickenpox - What is chickenpox?
Introduction
Chickenpox is an infection with a virus that causes an itchy rash. It usually goes away after a week or so, but for some people it can cause a serious illness.
We've brought together the best research about chickenpox and weighed up the evidence about how to treat it. You can use our information to talk to your doctor and decide which treatments are best for you.
Chickenpox is a condition that causes an itchy rash.
Most people get chickenpox when they're children. The rash can be uncomfortable, but chickenpox isn't usually dangerous. But for adults and young babies, or anyone who has another medical problem, chickenpox can be more serious.[1][2]
Chickenpox is caused by a virus. You catch it from other people who have it. You can get it if they cough or sneeze around you. You can also catch it from the fluid that comes out of the spots in the rash.[1][2]
Chickenpox is very easy to catch. If you haven't had it before and come into contact with someone who has it, there's a 9 in 10 chance that you'll get it.[1] You can catch chickenpox from someone a day or two before they know that they have it.[2]
If you don't know whether you've had chickenpox before, you can have a blood test to find out. If you've had chickenpox in the past, you'll probably be immune to it. This means you can't get it again.
Glossary
viruses
Viruses are microbes (tiny organisms) that need the cells of humans or other animals to exist. They use the machinery of cells to reproduce. Then they spread to other cells in the body.
For more terms related to Chickenpox

