Last updated: March 24, 2022

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Chickenpox (varicella) is a primary infection caused by the varicella-zoster virus (VZV) that occurs most frequently during childhood. The disease is highly contagious, with transmission taking place via airborne droplets or, less frequently, through direct skin contact with vesicle fluid. Chickenpox occurs only once, as VZV antibodies persist for life. In addition to fever, patients present with a highly pruritic rash covering the entire body (including the scalp). The rash is characterized by macules that rapidly develop into papules and then vesicles with an erythematous base before forming crusts. The simultaneous manifestation of the exanthem's different stages is a hallmark of the disease. In immunocompetent individuals, chickenpox resolves after about six days. Clinical diagnosis is made on the basis of the characteristic rash, although further tests may be necessary in atypical or complicated cases. Chickenpox is usually a self-limiting disease and only requires symptomatic treatment, which includes topical agents for pruritus. Antiviral therapy (e.g., acyclovir) may be indicated in high-risk groups in which a severe course is expected (e.g., adults and immunosuppressed patients). Complications are more common in high-risk groups and during pregnancy. Congenital chickenpox syndrome can lead to malformations with potentially fatal consequences. As a result of VZV persistance in ganglion cells, reactivation of the virus may occur when the immune system is compromised, presenting as shingles (herpes zoster). Routine vaccination against chickenpox is generally recommended. The first dose can be administered at the age of 12–15 months, while the recommended age for the second dose is 4–6 years of age.

  • Primarily occurs in children
  • Before vaccines were widely introduced, ∼ 90% of all children had been infected by the age of 15.


Epidemiological data refers to the US, unless otherwise specified.


Exanthem phase


Smear your herpes all over the TANK”: Herpes is detected by TzANcK smear.


The differential diagnoses listed here are not exhaustive.


Antiviral therapy



Central nervous system


Fetus (chickenpox during pregnancy)

Reye syndrome is a complication that develops in the course of viral infections such as chickenpox in association with salicylate use!


We list the most important complications. The selection is not exhaustive.

  • In healthy children, chickenpox infection generally has a benign course and heals without any consequences.
  • Residual scarring may occur because of excessive scratching or bacterial superinfection.
  • Immunosuppressed individuals are at a greater risk of the disease taking a generalized or even fatal course.


Chickenpox immunization

  • Vaccine: live, attenuated vaccine
  • Primary immunization
    • The CDC recommends two doses of the vaccine: first dose at 12–15 months of age ; ; second dose at 4–6 years of age (may be given earlier, but must be at least three months after the first dose)
  • Catch-up vaccination
    • Two doses of varicella vaccine recommended for all children without evidence of immunity between the ages of 7–18
    • After 18 years of age:
      • Individuals in close contact to individuals at high risk of infection (e.g., caretakers of immunocompromised patients)
      • Individuals at high-risk of exposure to infected individuals (e.g., childcare employees)
      • Before patients undergo immunosuppressive therapy or organ transplantation
      • Seronegative women of child-bearing age
      • Individuals with severe neurodermatitis

Postexposure prophylaxis of chickenpox

Postexposure prophylaxis may prevent disease onset or significantly mitigate the course of the disease.

  1. Active immunization (live, attenuated vaccine)
    • Indications: > 12 months of age, asymptomatic, non-immune and immunocompetent patient following exposure
    • Implementation: within 5 days following exposure
  2. Passive immunization (varicella-zoster immune globulin, or VZIG)
    • Indications:
    • Implementation: within 10 days following exposure (ideally within 4 days after exposure)

Mandatory reporting

  • Chickenpox is listed among the infectious diseases designated by the CDC as nationally notifiable.


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