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Chickenpox (Varicella)

What is chickenpox?

Chickenpox is a highly contagious disease that usually occurs during childhood.

The disease is caused by the varicella-zoster virus (VZV). Transmission occurs from person-to-person by direct contact or through the air by coughing or sneezing.

Until 1995, chickenpox infection was a common occurrence, and almost everyone had been infected by the time he or she reached adulthood. However, the introduction of the chickenpox vaccine in 1995 has caused a decline in the incidence of chickenpox in all ages, particularly in children ages one through four years. The varicella vaccine can help prevent this disease, and two doses of the vaccine are recommended for children, adolescents, and adults.

What are the symptoms of chickenpox?

Symptoms are usually mild among children, but may be life-threatening to adults and people of any age with weakened immune systems. The following are the most common symptoms of chickenpox. However, each individual may experience symptoms differently. Symptoms may include:

  • Fatigue and irritability one to two days before the rash begins

  • Itchy rash on the trunk, face, scalp, under the armpits, on the upper arms and legs, and inside the mouth. The rash appears in several crops; it starts as flat red spots and progresses to raised red bumps that then become blisters.

  • Feeling ill

  • Decreased appetite

The initial symptoms of chickenpox may resemble other infections. Once the skin rash and blisters occur, it is usually obvious to a doctor that this is a case of chickenpox. If a person who has been vaccinated against the disease is exposed, he or she may get a milder illness with less severe rash and mild or no fever. Always consult your doctor for a diagnosis.

How is chickenpox spread?

Chickenpox is spread by exposure to the saliva or other respiratory secretions of an infected person. It can also be spread by being exposed to the fluid from the blistering rash. Once exposed, the incubation period is typically 14 to 16 days, but it may take as few as 10 and as many as 21 days for the chickenpox to develop. Chickenpox is contagious for one to two days before the appearance of the rash and until the blisters have all dried and become scabs. The blisters usually dry and become scabs within four to five days of the onset of the rash. Children should stay home and away from other children until all of the blisters have scabbed over. It is important that infected individuals avoid immunosuppressed individuals, such as those with transplants, HIV, or those receiving cancer treatments.

Family members who have never had chickenpox have a high percent chance of becoming infected when another family member in the household is infected.

How is chickenpox diagnosed?

The rash of chickenpox is unique and the diagnosis can usually be made on the appearance of the rash and a history of exposure.

What is the treatment for chickenpox?

Specific treatment for chickenpox will be determined by your doctor based on:

  • Your overall health and medical history

  • Extent of the condition

  • Your tolerance for specific medications, procedures, or therapies

  • Expectations for the course of the condition

  • Your opinion or preference

Treatment for chickenpox may include:

  • Acetaminophen (to reduce fever). Children with chickenpox should NEVER be given aspirin. 

  • Topical lotion (to relieve itchiness)

  • Antiviral drugs (for severe cases)

  • Bedrest

  • Increased fluid intake (to prevent dehydration)

  • Cool baths with baking soda (to relieve itching)

Children should not scratch the blisters because it could lead to secondary bacterial infections. Keep fingernails short to decrease the likelihood of scratching.

Can you get chickenpox twice?

Most people who have had chickenpox will be immune to the disease for the rest of their lives. However, the virus remains dormant in nerve tissue and may reactivate, resulting in herpes zoster (shingles) later in life. Very rarely, a second case of chickenpox does occur. Blood tests can confirm immunity to chickenpox in people who are unsure if they have had the disease.

What complications are associated with chickenpox?

Complications can occur from chickenpox. Those most susceptible to severe cases of chickenpox are adults and people with impaired immune systems. Complications may include:

  • Secondary bacterial infections

  • Pneumonia

  • Encephalitis (inflammation of the brain)

  • Cerebellar ataxia (defective muscular coordination)

  • Transverse myelitis (inflammation along the spinal cord)

  • Reye syndrome. This is a serious condition marked by a group of symptoms that may affect all major systems or organs. Children with varicella should not be given aspirin because it increases the risk of Reye syndrome.

  • Death