This condition is caused by the varicella-zoster virus. You may get the virus by:

• Breathing in droplets from an infected person’s cough or sneeze.

• Having contact with fluids from the chickenpox rash.

• Touching something that has been exposed to the virus (has been contaminated) and then touching your mouth, nose or eyes.

This condition is more likely to develop in:

• People who have never had chickenpox.

• People who have never been vaccinated against chickenpox.

• Healthcare workers.

• People who live in or spend time in crowded places. These may include:

  • College students.

  • Teachers.

  • People in the army.

  • People who live in an institution, such as a prison.

• People who have a weakened disease-fighting system (immunesystem). You may have a weakened immune system if you:

  • Have HIV (human immunodeficiency virus).

  • Have AIDS (acquired immunodeficiency syndrome).

  • Have cancer.

  • Are receiving chemotherapy.

  • Are taking medicines that reduce (suppress) the activity of the immune system.

Symptoms of chickenpox are usually worse in adults than they are in children. Symptoms may include:

• An itchy rash that changes over time.

  • The rash starts as red spots, which then become bumps.

  • The bumps fill with fluid and become blisters.

  • The blisters crust and turn into scabs, usually about 3–7 days after the rash started.

• Body aches and pains.

• Headache.

• Tiredness.

• Fever.

Possible complications of chickenpox include:

• Skin infection.

• Lung infection (pneumonia).

• Brain infection or swelling (encephalitis).

• A bloodstream infection (sepsis).

• Bleeding problems.

• Dehydration.

• Problems with balance and muscle control (cerebellar ataxia).

• Having a baby with a birth defect, if you are pregnant.

This condition may be diagnosed based on:

• Your symptoms.

• Your medical history.

• A physical examination.

• Blood tests.

• Testing a fluid sample (culture) from the rash.

Treatment for this condition may include:

• Taking medicine to shorten the illness and make it less severe.

• Applying calamine lotion to relieve itching.

• Using baking soda or dry oatmeal baths to soothe itchy skin.

• Using a medicine that reduces itching (antihistamine).

• Taking antibiotic medicines if you also develop a bacterial infection. Antibiotics do notcure viral infections such as chickenpox.

Medicines

• Take or apply over-the-counter and prescription medicines only as instructed by your healthcare provider. These include any antihistamines and anti-itch creams.

• If you were prescribed an antibiotic, take it as instructed by your healthcare provider. Do not stop using the antibiotic even if you start to feel better.

Relieving pain, itching and discomfort

• Try to stay cool and out of the sun. Sweating and being hot can make itching worse.

• Cool baths can be soothing. Try adding baking soda or dry oatmeal to the water to reduce itching. Do not bathe in hot water.

• Put cold, wet cloths (cold compresses) on itchy areas as instructed by your healthcare provider.

• Use calamine lotion as recommended by your healthcare provider. This is an over-the-counter moisturising cream that helps to relieve itchiness.

• Do not eat or drink foods and beverages that are spicy, salty, or acidic if you have blisters in your mouth. Soft, bland and cold foods and drinks are easiest to swallow.

• Do not scratch or pick at the rash. To help avoid scratching:

  • Keep your fingernails clean and cut short.

  • Wear gloves or mittens while you sleep, if scratching is a problem.

Preventing infection

• You start to be contagious 1–2 days before the rash appears. You remain contagious until your blisters become crusted. While you are contagious, avoid being around:

  • Pregnant women.

  • Babies.

  • People receiving cancer treatments or long-term steroids.

  • People with weakened immune systems.

  • Older people.

  • Anyone who has not had chickenpox before.

  • Anyone who has not been vaccinated against chickenpox.

• Stay home from work or school until all blisters have crusted and new spots stop appearing, or for as long as instructed by your healthcare provider.

• If someone has been exposed to your chickenpox, contact a healthcare provider to see if that person needs to be vaccinated.

• Wash your hands often with soap and water for at least 20 seconds. If soap and water are not available, use hand sanitiser. Have others in your household also wash their hands often. Doing this:

  • Lowers your chance of getting a bacterial skin infection.

  • Lowers the chance that chickenpox will spread to others.

General instructions

• Drink enough fluid to keep your urine pale yellow.

• Rest as needed.

• Keep all follow-up appointments. This is important.