Varicella (chickenpox) is an acute infectious disease caused by the varicella-zoster virus (VZV), a DNA virus in the herpesvirus group,. Following primary infection, the virus persists as a latent infection in sensory nerve ganglia and can reactivate later in life as herpes zoster (shingles),.

• Transmission: The virus is highly contagious and spreads person-to-person via air (coughing/sneezing) or direct contact with vesicular fluid. It is communicable from 1–2 days before the rash appears until all lesions have crusted,.

• Incubation: Symptoms typically develop 10 to 21 days after exposure,.

• Symptoms: The hallmark symptom is an itchy rash that progresses rapidly from flat red spots (macules) to fluid-filled blisters (vesicles) and finally to ...