pediatrics
Erythema Infectiosum (Parvovirus B19 Infection)
Introduction
Erythema infectiosum is caused by acute infection with human parvovirus B19. In children, it causes mild constitutional symptoms and a blotchy or maculopapular rash beginning on the cheeks and spreading primarily to exposed extremities. In a fetus, it may be fatal. Diagnosis is clinical, and treatment is generally not needed. Erythema infectiosum, often referred to as fifth disease, is caused by human parvovirus B19. The name "fifth disease" is used because it is considered the fifth viral infection that commonly causes rash in children (the first four are measles, rubella, chicken pox, and roseola). It is also sometimes called slapped-cheek disease. It occurs mostly during the spring, commonly causing localized outbreaks every few years among children (particularly children aged 5 to 7 years). Spread seems to be by respiratory droplets and by percutaneous exposure to blood or blood products, with high rates of secondary infection among household contacts; infection can be asymptomatic. Infection may also occur in adults and may cause various clinical syndromes, including papular-purpuric gloves-and-socks syndrome, arthropathy, transient aplastic crisis, and pregnancy loss or Hemolytic Disease of the Fetus and Neonate . Based on seroprevalence surveys, 50 to 80% of adults have evidence of prior parvovirus B19 infection, which likely confers protective immunity for immunocompetent people. 