Warts
Warts on the bottom of the feet are called Plantar warts, or verruca plantaris. They are caused by the human papilloma virus, and are quite contagious. The human papilloma virus can live without a host for months, so it is very common to pick up this virus from walking barefoot on warm and moist public surfaces, similar to athlete's foot. Plantar warts are extremely painful on the soles of the feet, since all the weight exerted on the foot causes them to grow deep into the foot instead of outwards, and the sensation of having plantar warts on the feet has been likened to walking on sharp pebbles. Plantar warts are generally very harmless, however, they should be treated as soon as they are noticed to prevent possible pain and spreading of the virus. They are sometimes confused with corns, which look similar. The way to differentiate between the two is that the stritiae, or 'fingerprints' on the soles of the feet are disrupted and deformed in the case of a wart, but they simply continue on in the same pattern over a corn.Causes
Warts are caused by the human papilloma virus, a highly communicable virus. The virus is easily picked up on the feet by walking on warm and moist public surfaces, such as locker rooms, swimming pools, and steam rooms. To prevent plantar warts and a myriad of other undesirable viral, fungal, and bacterial skin infections, it is imperative that you always wear footwear when walking in public places!Warts are more common in children than adults since a natural immunity to some extent is formed eventually.