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exanthema subitum

[sōō′bĭ-təm]
n.
  1. A viral disease affecting infants and young children, characterized by a fever that lasts several days and a spotty rash that appears shortly after the fever has subsided.roseola infantum sixth disease
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.