Chickenpox is a contagious viral infection caused by the varicella-zoster virus (VZV). It typically causes an itchy rash with red spots and blisters all over the body, along with flu-like symptoms such as fever and fatigue. Chickenpox is highly contagious and spreads through direct contact with the rash or through respiratory droplets.

Most cases of chickenpox resolve on their own within a week or two without serious complications, especially in healthy children. However, it can be more severe in adults, newborns, pregnant women, and individuals with weakened immune systems.

Vaccination is highly effective in preventing chickenpox. The varicella vaccine, usually given in childhood as part of routine vaccinations, has significantly reduced the number of cases in countries where it is widely used.