Fifth disease

Alternative names:

"Slapped Cheek"; erythema infectiosum; parvovirus B19

Definition:

An acute viral disease characterized by mild symptoms and a blotchy rash beginning on the cheeks and spreading to the extremities.

Causes, incidence, and risk factors:

Fifth disease is caused by the human parvovirus B19 agent. It occurs most often during the spring with localized outbreaks in preschoolers or school-age children and adolescents. It is spread by respiratory secretions and the incubation period is to 12 days. The duration of the illness is usually five days. However, the rash may recur for several weeks and may be brought on by exposure to sunlight, heat, exercise, fever, or emotional stress.

Erythema infectiosum usually begins with bright red cheeks producing a "slapped-cheek" appearance. Following this a rash appears on the extremities and trunk. The rash fades centrally giving a lacy (reticulated) appearance to the rash. The rash fades over a period of one to two weeks. This illness is seldom associated with fever.

Parvovirus B19 is thought to cause other disease manifestations. In healthy adults it may be responsible for an infectious arthritis (particularly in women). In individuals with AIDS (or other immunocompromised persons) it may produce a profound anemia. This form of anemia is called 'transient aplastic crisis'.

The incidence of parvovirus B19 infection is unknown but studies suggest that 40 percent to 50 percent of adults have antibodies to the virus; this indicates a high degree of infection and also suggests that many infections go unnoticed.