Slapped cheek disease or Fifth disease

Slapped cheek disease is a viral disease. It gets this name because, early in the infection, the child's cheeks may be bright red, as if they have been slapped. Other names for this illness are Fifth disease (there used to be six childhood rashes recognised at the turn of the century and this was the number five) and erythema infectiosum (Latin for infectious rash).

What causes it?

The causative virus is called parvovirus B 19. An Australian, Professor Yvonne Cossart first described this virus which is different from the parvovirus of dogs and cats. The virus is transmitted in droplets coughed out by infected children.

Who gets it?

Fifth disease mainly affects school and pre-school aged children, and not uncommonly causes outbreaks in schools. Most adults are immune, having already had the infection when they were children.

What does it cause?

In Fifth disease, children may get a runny nose, fever, aches and pains, and rash. At first the rash may be on the cheeks (slapped cheek appearance). After a few days a rash may be found on the arms, legs or trunk. It is pink, has a lacy appearance and may be itchy. It may fade easily, but re-appear after a bath or exercise. Older children and adults may sometimes get swollen joints (arthritis) which get better after a few days.

Can the illness be serious?

Most people get Fifth disease when they are children and cannot get it again. In most children, Fifth disease is a mild, flu-like illness, which gets better on its own in a few days.

If a pregnant woman becomes infected, the unborn baby can be severely affected. Pregnant women in contact with a child with Fifth disease should see their doctor for blood tests and monitoring of their pregnancy.

Children with haemolytic blood disorders (sickle cell anaemia, thalassaemia) and children with leukaemia can get serious problems from the virus that causes Fifth disease.

What is the treatment?

Paracetamol is useful to relieve your child's aches and pains. Your child should see a doctor if they have any swollen joints or pain not relieved by paracetamol.

Infectious period

The incubation period for this illness is approximately 1 - 2 weeks. Fifth disease is no longer infectious once the rash appears.