Varicella, often referred to as chickenpox, is a widespread acute infectious condition triggered by the varicella-zoster virus (VZV). It manifests with systemic symptoms and distinct skin and mucosal eruptions, including macules, papules, and vesicles. Although it mainly affects children, the disease is typically more severe in teenagers and adults. Following the adoption of vaccine-based control measures in China, there has been a noticeable trend of varicella affecting older demographics, leading to an uptick in cases among teenagers and adults. This review synthesizes the latest research on the clinical symptoms, epidemiological trends, and immunization strategies for varicella in these age groups, both domestic and aboard. The goal is to enhance strategies for prevention and control, support the development of tailored immunization policies, and underscore the critical role of the varicella vaccine in comprehensive health management across all ages.