Bumps can occur in a variety of clinical conditions, such as urticaria due to allergies, which mostly appear as bumps on the skin, either in isolation or fused with each other and accompanied by varying degrees of itching. They can also be caused by infections, such as common warts or flat warts caused by human papilloma virus, and can appear as enlarged bumps of varying sizes. Molluscum contagiosum can also be caused by infection with the molluscum contagiosum virus, which is an isolated, scattered wart-like protrusion on the surface of the skin with a smooth surface. It may also be a bacterial infection that causes folliculitis, which is primarily an inflammatory manifestation.