A verruca or verrucae (plural) is simply a wart on the foot.

Verrucae are caused by the Human Papilloma Virus and will only resolve when the immune system recognises them as a problem which can take months and sometimes years. The current evidence based research supports a treatment regime of masterly inactivity, in other words leave well alone until they resolve.
Treatments are often costly and painful so we prefer not to treat with acids, caustics etc.

In terms of spread the majority of Podiatrists, Dermatologists and skin specialists, are not in favor of treating verrucae. Many feel that because the virus is so widespread, it could be beneficial to spread it as much as possible and as early as possible in the lives of children in order to build up immunity. 

Verrucae are not usually painful, however the overlying callus (hard skin) can be uncomfortable in which case, book an appointment to have the callus removed and for advice on how to self-treat in order to stimulate the immune response required.