Papular urticaria Papular urticaria is more common in spring and autumn. It may clear up on holiday or on moving house. One or several members of the family may be affected. Occasionally the eruption can clear up for years and then recur unexpectedly. It is not associated with any internal complaint and is never a serious disease.
Papular urticaria is thought to be an allergic reaction to insects in the environment.
Often after a few years the person becomes desensitized to these insects and the reaction dies down. A bite isn't usually noticed and it is thought that the reaction can occur simply from skin contact with parts of the insect such as its faeces and eggs - this accounts for spots in unexpected places. The most common identified causes are insects that live on cats and dogs, such as fleas and mites. Fleas are easily seen with the naked eye but can be difficult to get rid of. Mites are too small to see but are equally common.