My son had a plantar wart on his foot, which (as I understand it) is caused by a virus which only infects skin cells. Once in the skin cell the virus replicates, but when attacked by the immune system prompts the growth of a hard, thick layer of skin (callus). Warts are caused by a HPV.

Given the wart has infected a skin cell, and skin cells are next to each other in a great big sheet covering the entire human body, why is it that we don't become completely covered in wart? I assume that it's not the immune system keeping the wart at bay, because the original wart isn't defeated and we can get other spot infections elsewhere.

  • $\begingroup$ The Wikipedia page you link to says that they are self-limiting, although it doesn't say why. $\endgroup$
    – canadianer
    May 28 '14 at 6:44
  • 1
    $\begingroup$ actually there is a person who was completely covered with warts; not as a homogeneous sheet, though. Watched the video on youtube. $\endgroup$
    May 28 '14 at 6:46

Plantar warts grow deep into the skin and slowly [1]. It is a common thing for warts to multiply [1], but because of the slow growth speed, their symptoms [2] and the self clear-up [1] they can't end up by covering the entire skin surface of a previously healthy person.

There are cases of generalized warts in patients with immune deficiency like hypogammaglobulinaemia, impairment of cell mediated immunity [3]. The immune system plays an important role in limiting warts. There is also a case of generalized facial warts in a patient with no other known medical condition [4].


  1. American College of Foot and Ankle Surgeons, Plantar Wart (Verruca Plantaris)
  2. MAYO Clinic, Diseases and Conditions - Plantar warts.
  3. Reid TM, Fraser NG, Kernohan IR. Generalized warts and immune deficiency. Br. J. Dermatol. 1976 Nov;95(5):559-64. PubMed PMID: 1086679.

  4. Semon H. Papillomatosis: Generalized Facial Warts. Proc. R. Soc. Med. 1935 Dec;29(2):90. PubMed PMID: 19990539.

  • 1
    $\begingroup$ Your reference for "self clear-up" only indicates that this is a possibility, not a certainty, and doesn't discuss the mechanism. "Generalized warts and immune deficiency" was informative, and suggests that en.wikipedia.org/wiki/Antigenic_variation is the cause of subsequent infections. $\endgroup$
    – Josh
    Jun 2 '14 at 23:26

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.