A rash that usually begins on the body and face and later often spreads to the scalp and limbs.
It may also spread to the mucous membranes especially in the mouth and on the genitals.
The rash is often itchy.
It begins as small red spots which develop into blisters in a couple of hours.
After one or two days, the blisters turn into scabs.
New blisters may appear after three to six days.
The number of blisters differs greatly from one person to another.
The infected person may run a temperature.
These symptoms are mild in young children.
Chickenpox lasts 7 to 10 days in children and longer in adults.
Adults can feel very ill and take longer to recover. They are also more likely than children to suffer complications.

Pregnant women who have not had chickenpox.
People with a weak immune system, such as those with acute or chronic leukaemia or HIV.
Patients taking medicine to suppress their immune system, such as long-term oral corticosteroids.