Varicella Zoster Virus (VZV) is a highly contagious virus that causes chickenpox, a common childhood illness characterized by an itchy rash and flu-like symptoms. After the initial infection, VZV can remain dormant in the body and may reactivate later in life, leading to shingles, a painful rash that usually appears on one side of the body. Vaccination is an effective way to prevent chickenpox and its complications. The varicella vaccine is recommended for children and can also protect adults who have never had chickenpox. Understanding VZV helps in managing outbreaks and protecting vulnerable populations, such as infants and those with weakened immune systems.