Varicella (Chickenpox): Symptoms, Causes & Treatment

Chickenpox (varicella) is a highly contagious viral disease caused by the varicella-zoster virus, the same virus that may reappear later in life causing shingles. It is marked by an itchy rash that develops from red spots into small fluid-filled blisters that then crust over, appearing in crops across the body.

The virus spreads easily through respiratory droplets and contact with blister fluid, so it spreads quickly among children in schools and nurseries. It was among the most common childhood diseases before the vaccine became available, and remains common where vaccination coverage is low.

Most chickenpox cases in healthy children are mild and recover within one to two weeks with supportive care and itch relief. However, the disease can be more severe and dangerous in adults, pregnant women, infants, and the immunocompromised, and may cause complications such as bacterial skin infections or pneumonia. The vaccine remains an effective means of prevention and reducing disease severity, with the importance of avoiding scratching the blisters to prevent infection and scarring.

• An itchy rash that develops into fluid-filled blisters then crusts.
• Fever, fatigue, and headache.
• Loss of appetite.
• The rash appears in crops at different stages together.

• Infection with the varicella-zoster virus.
• Spread through respiratory droplets and contact with blister fluid.
• Lack of immunity from not being vaccinated or not previously infected.

• Clinical diagnosis from the characteristic rash and its stages.
• Tests to confirm the virus when needed or in atypical cases.

Supportive care

• Fever reducers (avoid aspirin in children), anti-itch remedies, and lukewarm baths.
• Trimming nails and avoiding scratching to prevent bacterial infection and scarring.

At-risk groups

• A doctor may prescribe an antiviral for adults, severe cases, or the immunocompromised.

This content is educational and does not replace medical advice.

• Bacterial skin infections from scratching.
• Pneumonia, especially in adults.
• Risks to a pregnant woman and the fetus.
• Later reactivation of the virus as shingles.

• The chickenpox vaccine.
• Isolating the patient until all blisters crust over.
• Avoiding contact with pregnant women and the immunocompromised during infection.