A virus called varicella-zoster virus (VZV) causes this illness. It spreads through:

  • Breathing airborne droplets that have the VZV virus
  • Direct contact with fluid from a chickenpox rash

A pregnant mother can also pass it to her fetus.

Risk Factors

The main risk factor is contact with someone who has chickenpox. It is most common in children under 10 years of age. It is also more common in winter and spring. Other things that may raise the chance of chickenpox infection are:

  • No history of chickenpox infection in the past
  • No history of chickenpox (varicella) immunization
  • Health problems or medicines that lower the ability to fight infection, such as cancer, HIV infection, or an organ transplant
  • Maternal exposure during pregnancy



Symptoms start about 10 to 21 days after contact. They are worse in adults.

First symptoms may be:

  • Mild headache
  • Mild fever
  • Cough
  • Sore throat
  • Severe itch
  • Lack of hunger
  • Belly pain

The rash appears within 1 to 2 days after the first symptoms. The rash:

  • Starts with small, flat, red spots:
    • Spots become raised and form a round, very itchy, fluid-filled blister
    • Blisters happen in clusters, with new ones forming over 5 to 6 days
  • Starts in patches on the skin above the waist, such as the scalp
  • May also appear on the eyelids, in the mouth, upper airway, or voice box, or on the genitals
  • Crusts over by day 6 or 7 and goes away within 3 weeks


The doctor will ask about your symptoms and past health. A physical exam will be done. The rash is often enough to make the diagnosis.



Chickenpox is mild in most people. It will pass on its own. In most, it will last for 1 to 3 weeks. Others may have serious problems from it.

The goal of treatment is to manage symptoms. Choices are:

  • Supportive care, such as wet compresses
  • Medicines to:
    • Ease itching, such as over the counter creams or lotions or oral antihistamine medicine
    • Shorten the infection and severity of the infection, such as antiviral medicine or varicella-zoster immune globulin


To lower the risk of this problem:

  • Avoid being around anyone who has chickenpox
  • Get the chickenpox vaccine

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.