Chickenpox, also called varicella, is an acute viral disease. It is caused by the varicella-zoster virus. Symptoms include fever, general malaise, and a rash which begins with small reddish bumps (papules) that quickly fill with fluid to form small blisters (vesicles).
Review Date 7/8/2023
Updated by: Linda J. Vorvick, MD, Clinical Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.