Warts are sores on the skin that resemble small to medium sized lumpy calluses. They are caused by a skin virus that infects the body through a break or crack in the skin. Warts on the foot can be particularly painful as they form a thick callus that receives constant pressure with walking, although some warts are painless. The virus directs skin cells to create thick callus tissue which folds in and out, creating a cauliflower-like appearance. The virus also may lie dormant in the skin surrounding the wart, hidden from view.
Warts can spread from one person to another via shed skin cells, and the most common areas of infection are locker rooms, shower stalls, bathrooms, and other public places barefoot individuals are present. The body does not generally react to the presence of the virus on its own as the infection is limited to the top layers of the skin. Most viruses will circulate throughout the body, which will trigger some type of defense mechanism in the body’s immune system and the formation of antibodies which destroy that specific virus. The skin wart virus will not generally cause this reaction, and treatment is usually necessary to create this immune reaction and eradicate the wart.
Currently there is no true medical cure for foot warts. They may be extremely resistive to treatment. However, as stated above, the body has an excellent mechanism for destroying the virus once it is stimulated into responding. Therapy involves removing the calloused skin and applying acids or other chemicals that either dissolve the warty material or increase skin exfoliation. This activity causes a generally painless local skin inflammation that activates the body’s immune system. Eventually, the body’s immune system recognizes the virus and eradicates it by creating circulating antibodies, which will destroy the virus. Freezing the skin can also be beneficial, although it is generally less effective than similar treatment for hand warts and requires a direct, potentially painful application of pure liquid nitrogen to freeze the thicker foot skin. Surgical excision with cauterization or laser therapy to the wart base may also be considered, but there is a possibility of reinfection due to the continued presence of untreated dormant virus hidden in the skin surrounding the treated wart.
With an effective immune response, most patients are permanently cured of the viral infection, as the body circulates antibodies to the virus strain which will immediately destroy the virus once it is encountered. Unfortunately, there are over fifty different strains of virus that can cause warts. The good news is that exposure to a wart virus is uncommon, unlike contracting a common cold virus, and simple precautions like wearing sandals in public showers or locker rooms will help prevent exposure. If a wart is noticed on the foot, it is better to have it treated early on as waiting can make the wart more likely to be resistant to treatment, and to spread.