Final answer:
Varicella, or chickenpox, is a contagious viral disease characterized by pustular lesions on the trunk. It is easily transmitted and primarily affects children.
Step-by-step explanation:
Varicella, also known as chickenpox, is a contagious viral disease caused by the varicella-zoster virus. It is characterized by the formation of pustular lesions on the trunk. The disease is easily transmitted through direct contact or inhalation of material from the skin lesions. It primarily affects children but can also be more severe in adults.