Fifth disease, also called erythema infectiosum, is a viral infection caused by human parvovirus B19. It occurs most commonly in children with up to 70% of all cases occurring in children 5 to 15 years old.
Called fifth disease because it was historically the fifth childhood infectious rash to be named, this viral infection occurs worldwide but is more common in temperate climates. Epidemics are seasonal with most outbreaks occurring in the winter and spring. The infection seems to be more common in girls than boys.
There is no vaccine for fifth disease. However, once you're infected with the virus, you're immune for life against future infections.