What is fifth disease? What does fifth disease cause?
Fifth disease is a mild rash illness that occurs most commonly in children. Historically, it was called fifth disease because it was the fifth of a group of once common childhood diseases with similar rashes. It is caused by a parvovirus B19 (not the same one that causes disease in animals). A parvovirus infection can be more serious for pregnant women and for adults with some kinds of anemia or who have a compromised immune system.
