Erythema infectiosum, or "The Fifth Disease," is a poorly understood illness which can easily be recognized in epidemics. In nonepidemic situations recognition is possible but more difficult, frequently resulting in unnecessary treatment, extended absence from school, and undue concern on the part of both the physician and parent. This paper is presented as a reminder that this disease does exist as well as to define some of its epidemiologic characteristics.
In January, 1963 (following the Christmas holidays), small outbreaks of a mild exanthematous illness were reported from several areas of the country. An outbreak of illness with the same characteristics developed among many children of an elementary school in Circleville, Ohio. Histories and physical examinations performed by us on 38 affected children elicited symptoms and signs compatible with erythema infectiosum. A questionnaire sent to parents of all students attending the school provided information for 286 households, with a