Flat warts are generally caused by the human papilloma virus, which has more than 100 subtypes. Flat warts are usually caused by papillomavirus type 3 infections and are more common on the face or back of the hands. Warts on the face can appear as small brown or skin-colored bumps, slightly raised, with a smooth surface, and can appear singly, densely packed, or even fused into a large area. Some patients may experience itching and new warts may develop without their awareness. The most important thing is that you can see the warts on your face in the form of beads, which can be considered as an acute attack of warts. Any minor irritation can trigger the aggravation of flat warts.