That painful bump on your foot is likely a virus, not a callus.

Health · Published 29 September 2026 Swipe more like this →

In short: Plantar warts are common, benign skin growths caused by specific strains of the human papillomavirus. While often mistaken for calluses, these lesions are distinct, frequently painful, and can persist for years. Understanding how they spread and when to seek professional care is key to managing these stubborn viral invaders.

Plantar warts, or verrucas, are benign epithelial tumors that develop on the soles of the feet or toes. They are caused by infection from various strains of the human papillomavirus (HPV), most commonly types 1, 2, 4, 60, or 63. Unlike calluses, which are caused by friction, these warts occur when the virus enters the skin through tiny cuts or abrasions. Because of the pressure from walking, the wart is often pushed inward, forming a layer of hard skin over the lesion.

Distinguishing a plantar wart from a corn or callus is essential. While both can be painful, plantar warts disrupt the natural friction ridges of the skin—the foot's equivalent of a fingerprint—whereas these striations continue uninterrupted across a callus. Furthermore, plantar warts are typically sensitive to pressure applied from the sides of the lesion, while corns are more painful when direct pressure is applied. They often feature tiny black dots on the surface, which are actually small hemorrhages under the skin.

While many plantar warts resolve on their own within a few years, treatment is recommended if they cause pain or distress. Options range from over-the-counter salicylic acid, which peels away dead skin cells, to professional interventions like cryotherapy, which freezes the tissue, or surgical excision. Because these warts are contagious, they can spread through direct contact or contaminated surfaces like communal showers. Simple precautions, such as wearing flip-flops in public changing areas and covering warts with plasters while swimming, can help prevent transmission to others.

It is important to note that standard HPV vaccines, such as Gardasil and Cervarix, do not prevent plantar warts. These vaccines target strains associated with other conditions, whereas plantar warts are caused by different viral types. If a lesion is large, painful, bleeds, or changes in appearance, consulting a healthcare professional is advised to ensure proper diagnosis and avoid potential complications or misidentification.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

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