From the Guidelines
Varicella, commonly known as chickenpox, is a highly contagious viral infection caused by the varicella-zoster virus that can be effectively prevented with vaccination, as demonstrated by a significant decline in incidence, hospitalizations, and deaths since the implementation of the varicella vaccination program in 1995 1.
Key Characteristics of Varicella
- It typically affects children and presents with an itchy rash of fluid-filled blisters that appear in crops over the body, face, and scalp, accompanied by fever and general malaise.
- The virus spreads through direct contact with the rash or through airborne droplets when an infected person coughs or sneezes.
- Most cases resolve within 1-2 weeks without specific treatment, though acetaminophen can help reduce fever and calamine lotion or oatmeal baths may relieve itching.
Prevention and Vaccination
- Vaccination is now widely available and recommended for children, typically given in two doses at 12-15 months and 4-6 years of age, as approved by the Advisory Committee on Immunization Practices (ACIP) in June 2006 1.
- The varicella vaccine is approximately 85% effective in preventing varicella and >95% effective in preventing severe varicella disease 1.
- The routine 2-dose recommendation for children has been shown to significantly reduce the burden of varicella disease and its complications, making it a crucial tool in preventing morbidity and mortality associated with the infection 1.
From the Research
Definition of Varicella
- Varicella, also known as chickenpox, is a common and highly contagious exanthematic disease caused by the varicella-zoster virus (VZV) 2, 3, 4, 5, 6.
- It is characterized by a mild to moderate illness in healthy immunocompetent subjects, particularly children, but can be severe in immunocompromised individuals, infants, and adults 2, 3, 4, 5, 6.
Causes and Transmission
- Varicella is caused by primary infection with VZV, which can establish latency in ganglionic neurons 2, 3, 4, 5, 6.
- The virus can reactivate decades after primary infection, causing herpes zoster (shingles) 2, 3, 4, 5, 6.
- Varicella is highly contagious and can be prevented by vaccination with an attenuated vaccine administered around the first year of age, and with a boost vaccination in school age 3.
Complications and Risks
- Serious complications can occur, particularly in pregnant women, unborn children, neonates, and those who are immunocompromised 4, 5, 6.
- Reactivation of the virus can lead to persistent radicular pain (postherpetic neuralgia), myelitis, cranial nerve palsies, meningitis, stroke, retinitis, and gastroenterological infections 6.