✤ Warts are caused by a virus, and verrucas are just warts on the feet.
✤ You can spread warts on yourself by picking them. They usually go away within two years, and the treatments can cause blisters and infections, which can be worse than warts.
✤ Painting them with salicylic acid (bought from chemists) daily for 12 weeks, will kill two-thirds of warts but requires dedication and precision. Over-the-counter freeze sprays may not make the warts cold enough to kill them, but while cryotherapy carried out by a doctor will hurt and blister, it can work. Warts on the face, that spread or persist, should be seen by a doctor.