Slapped cheek syndrome or fifth disease is a viral infection most commonly affecting children aged between 3 and 15 years. Diagnosis is usually based on symptoms and clinical features which most commonly involves the appearance of a distinct blotchy red rash across the cheeks accompanied by a sore throat, fever, headaches and upset stomach.

Infection in adults

In adult cases of infection, the symptom is typically joint pain and stiffness and the absence of the distinctive red cheeks means diagnosis may be missed at first in adults. To confirm diagnosis, a chest X-ray may be performed to check for infection and blood tested for antibodies to the virus.

High risk groups

Blood tests are also recommended for individuals who are at high risk of serious complications of infection. These include:

• Pregnant women who are not immune. The virus affects the ability of the blood marrow to make red blood cells and can cause severe anaemia in the foetus and even cause stillbirth or miscarriage. A blood transfusion may be needed if the baby is born with severe anaemia.
• Those with blood cell disorders such as sickle cell disease or thalassaemia. These people are more prone to anaemia in the first place and so are likely to have a more severe loss of red blood cells (refereed to as apastic crisis) which requires immediate treatment.
• Those with a weak immunity such as individuals with HIV, those undergoing chemotherapy or elderly individuals, as infection may be more serious and prolonged.

Treatment

There are no known vaccines that can protect against slapped cheek syndrome. The infection itself is mild and self remitting and usually resolves within a week without complications while providing the child with a lifelong immunity against the virus.

However, the illness may be managed in the following ways:

• Children may be given plenty of fluids and bed rest and be isolated from other children, especially during the first week after contracting the infection.
• Ibuprofen or paracetamol may relieve joint pain, fever and headaches. Children under the age of 16 should not be given aspirin due to the associated risk of Reye's syndrome - a condition which can cause significant brain and liver damage.
• Antihistamines such as levocetirizine, azelastine, loratidine can be used to relieve itchy rashes. Calamine lotion may also relieve itchiness.