Chickenpox

Chickenpox is a common illness that mainly affects children and causes an itchy, spotty rash.

Most children will catch chickenpox at some point. It can also occur in adults who didn't have it when they were a child.

It's usually mild and clears up in a week or so, but it can be dangerous for some people, such as pregnant women, newborn babies and people with a weakened immune system.

Symptoms of chickenpox

The symptoms of chickenpox start one to three weeks after becoming infected.

The main symptom is a rash that develops in three stages:

• spots – red raised spots develop on the face or chest before spreading to other parts of the body
• blisters – over the next few hours or the following day, very itchy fluid-filled blisters develop on top of the spots
• scabs and crusts – after a further few days, the blisters dry out and scab over to form a crust; the crusts then gradually fall off by themselves over the next week or two

Chickenpox is contagious until all the blisters have scabbed over, which usually happens about five or six days after the rash appeared.