A type of rash characterized by a flat, red area on the skin that is covered with small confluent bumps. It is common in several disesases and medical conditions includign scarlet fever, measles, rubella and Ebola, as well as a common manifestation of a skin reaction to a number of drugs including the antibiotic amoxicillin and the antiepileptic drug lamotrigine. The disease is maculopapular eruption (EFO_1001253, an Experimental Factor Ontology id). Also known as: maculopapular rash.