With prolonged diarrhoea and failure to thrive, the stool should be tested for infection, and referral to a paediatrician should be considered. In children this is a mild illness which causes fever and crops of spots. These mature from a papule to a blister, which then dries and scabs. The rash is central, affecting mainly the trunk and head. The arms and legs are more or less spared.
Treatment consists of soothing cream and paracetamol.
Pneumonia is a rare complication.