Chickenpox is the common name for Varicella zoster. Historically one of the childhood infectious diseases caught by and survived by almost every child, a non-permanent varicella vaccine has been available and used since 1995 to inoculate against the disease. ...

Chickenpox is the common name for Varicella zoster. Historically one of the childhood infectious diseases caught by and survived by almost every child, a non-permanent varicella vaccine has been available and used since 1995 to inoculate against the disease.

Chickenpox is caused by the varicella-zoster virus (VZV), also known as human herpes virus 3 (HHV-3), one of the eight herpes viruses known to affect humans. It starts with conjunctival (eye discharge) symptoms and then characteristic spots appearing in two or three waves, mainly on the body and head rather than the hands and becoming itchy raw pox (pocks), small open sores which heal mostly without scarring.

Chickenpox has a 10-21 day incubation period (time between being infected and showing symptoms) and is highly contagious through physical contact two days before symptoms appear. Following primary infection there is usually lifelong protective immunity from further episodes of chickenpox.

Chickenpox is rarely fatal (usually from varicella pneumonia), with pregnant women and those with a suppressed immune system being more at risk. Pregnant women not known to be immune and who come into contact with chickenpox may need urgent treatment as the virus can cause serious problems for the fetus. This is less of an issue after 20 weeks.

Later in life, viruses remaining dormant in the nerves can reactivate causing localised eruptions of shingles. This occurs particularly in people with compromised immune systems, such as the elderly, and perhaps even those suffering sunburn. Unlike chickenpox which normally fully settles, shingles may result in persisting post-herpetic neuralgia pain.