fifth disease

American  

[fifth di-zeez] / ˈfɪfθ dɪˌziz /

noun

1. Pathology. a mild infection, most often seen in children or young adults, caused by a small virus (the human parvovirus B19) and marked by a blotchy rash on the cheeks, arms, and legs.

---

fifth disease British  

noun

1. Technical name: erythema infectiosum.  Also called: slapped-cheek disease.  a mild infectious disease of childhood, caused by a virus, characterized by fever and a red rash spreading from the cheeks to the limbs and trunk

---

Etymology

Origin of fifth disease

So called because it was the fifth in a classification scheme of childhood eruptive diseases