Fifth disease

Fifth disease is a common childhood infection causing a slapped cheek appearance and a rash. It is also known as erythema infectiosum.

Fifth disease is caused by Parvovirus B19. It most commonly affects young children and often occurs in several members of the family or school class. Thirty percent of infected individuals have no symptoms.

Fifth disease

Family affected by parvovirus

What are the symptoms of fifth disease?

The first sign of fifth disease is firm red cheeks, which feel burning hot. A rash follows 1 to 4 days later with a lace or network pattern on the limbs and then the trunk.

The child with fifth disease is usually otherwise quite well, but may have a slight fever and headache.

Although most prominent in the first few days, the rash can persist at least intermittently for up to six weeks.

Fifth disease

Slap cheeks

Slap cheeks

Lace-pattern of rash

Complications

Rarely fifth disease results in complications.

• Arthritis in infected adults
• Aplastic crisis in patients with blood disorders (potentially dangerous low blood cell count)
• Intrauterine death (9%) or hydrops fetalis in 3% of the offspring of infected pregnant women can occur if the infection occurs in the first half of pregnancy. However, congenital malformations do not occur. As the risk of an adverse outcome is very low, the infection is not routinely screened for in pregnancy.

Diagnosis

The characteristic slapped cheek and lacy rash in a child who is otherwise well usually make the diagnosis. The parvovirus can cause other rashes such as a glove-and-stocking rash. In case of doubt, a blood test can be done to confirm the presence of current parvovirus infection or immunity to it. If the child is unwell, or has a blood disease, a full blood count should be performed. Ultrasound examination of at-risk pregancies can detect hydrops fetalis (which requires intrauterine transfusion).

Treatment

Fifth disease is not generally a serious condition. There is no specific treatment. Affected children may remain at school as the infectious stage occurs before the rash is evident The application of an ice-cold flannel can relieve the discomfort of burning hot cheeks.