Last edited 11/2018

Viral warts are benign papillomas caused by infection of the keratinocytes by human papilloma viruses (1).

  • prevalence in the general population is estimated to be between 7-12% (2)
  • commonly seen  in childhood, but can occur at any age
    • small cohort observational studies have suggested that 5–30% of children and young adults have warts (1)

HPV is usually transmitted by direct skin-to-skin contact. Indirect transmission via contact with contaminated surfaces also may occur. Incubation period may last from 1 month to 2 years (3).

Risk factors include:

  • immunosuppression
  • close contact with affected people
  • damaged epithelial barrier e.g. -
    • plantar warts transmitted from swimming pools due to the rough surfaces abrading the skin of the feet
    • nail biting - periungual warts
    • shaving – spreads warts over the beard area
    • along the sites of trauma – warts may develop in these sites, known as the Koebner phenomenon (2,3).

If the immune system is compromised they can present major problems to cure.