In modern times, rashes are usually caused by viruses. The rash usually lasts for a few days before disappearing without any ill effects. Apart from the rash, the child may feel unwell with a fever, lack of interest and loss of energy. Sometimes diarrhoea and a runny nose can occur. Complications of these infections are very rare in healthy children and the problem is almost always mild.
Most children go about their normal play as though nothing is wrong.
The virus usually spreads from person to person by close contact mainly by the breath. There are three main types which are simply called fourth, fifth and sixth disease. The term 'disease' is not a good one as they are not really diseases. This common problem can be caused by a number of viruses, especially those affecting the bowel. The rash is so much like rubella that it is often misdiagnosed as rubella.