WHEN IS IT INFECTIOUS?

From 4 days before rash appears to after last lesion has scabbed. Scabbed lesions are not infectious.

WHAT IS THE RASH LIKE?

The rash usually appears 2 days after general cold-like symptoms and fever. Starts on chest and back - spreads to cover whole body over 2 days. Spots start as red patches, develop a clear blister, and then scab over.

HOW LONG DOES IT TAKE TO DEVELOP?

The incubation period is 12 - 21 days from being in contact the illness to becoming ill.

WHAT IS THE TREATMENT?

The itching is best treated by keeping cool. Calamine lotion, anti-histamines and sodium bicarbonate in a cool bath may all be tried. Keeping the skin clean may help prevent the spots becoming infected.

As with all fevers it is important to drink plenty, and regular paracetamol will help reduce the fever and discomfort. Spots may occur inside the mouth, and a mouthwash can be more comfortable than brushing the teeth.

WHAT IF YOU'RE PREGNANT?

Most adults are immune (80-90%) having had chicken pox infection in the past. A pregnant woman who is unsure of her immunity can have a rapid blood test done. Non-immune women need injections (zoster immunoglobulin) or tablets (acyclovir) which can reduce the infection. Infection may be transferred across the placenta to the foetus. In early pregnancy (first 5 months) this is fortunately very rare (2%). If chicken pox is contracted a week before to a month after delivery there is a risk that the newborn baby may get chickenpox, and this will need specialist advice on treatment for the baby.

The risks to a pregnant woman with chicken pox of associated pneumonia are higher, and this can be serious.

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