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Chickenpox is a viral infection. It is highly contagious. It creates a widespread, itchy rash. The infection can also cause serious complications in some people. Chickenpox is more dangerous for adults and newborns. It is also a danger for people with suppressed immune systems.

Chickenpox

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Chickenpox is caused by the varicella-zoster virus (VZV). It spreads from person to person via:

• Airborne droplets of moisture containing the VZV virus
• Direct contact with fluid from a chickenpox rash

It is contagious 1-2 days before the rash erupts. It remains contagious until all of the blisters have crusted. This takes five days. It is most contagious just after the rash has broken out.

A pregnant mother can transmit the virus to a fetus.

Factors that increase your chance of getting chickenpox include:

• Close contact with an infected person, unless you have been vaccinated, or have already had chickenpox
• Age: less than three years old, with peak incidence between 5-9 years old
• Immune-deficient state, such as having leukemia, an organ transplant, high-dose steroid, or HIV
• Cancer
• Pregnancy
• Time of year (late winter, early spring)

Symptoms break out about 10-21 days after contact. They are more severe in adults than they are in children.

Initial symptoms include:

• Mild headache
• Moderate fever
• Cough
• Sore throat
• Severe itch
• Lack of appetite
• General feeling of malaise
• Some children complain of abdominal pain

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

• Consist at first of small, flat, red spots:
  • Spots become raised and form a round, intensely itchy, fluid-filled blister
  • Blisters develop in clusters, with new clusters forming over 5-6 days
• Usually develop into crops on the skin above the waist, including the scalp
• May also appear on the eyelids, in the mouth, upper airway, voice box, or on the genitals
• Typically crusts over by day six or seven and disappears within three weeks

The doctor will ask about your symptoms and medical history. A physical exam will be done. Diagnosis is usually based on the rash and your age. Blood and lab tests to identify the virus are rarely needed.

Chickenpox is mild in most people. It will naturally run its course. In these cases, treatment focuses on relieving the symptoms.

Avoid contact with anyone who has chickenpox. This is very important if you have not been vaccinated against the infection.

If you or your child has not been vaccinated, but are exposed to chickenpox, a vaccine given right away may help lessen the severity of the infection, or prevent the infection.