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.
Origin of fifth disease
so called because it was the fifth in a classification scheme of childhood eruptive diseases
Also called er·y·the·ma in·fec·ti·o·sum [er-uh-thee-muh in-fek-shee-oh-suh m] /ˌɛr əˈθi mə ɪnˌfɛk ʃiˈoʊ səm/
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
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 trunkAlso called: slapped-cheek disease Technical name: erythema infectiosum
Word Origin for fifth disease
C20: from its being among the five most common childhood infections
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