HPV is an infection that causes warts. There are more than 100 strains of the human papillomavirus and more than 40 strains of HPV affect the genital area.

Different strains of HPV infection can cause warts on different parts of the body. Some types of HPV infection cause plantar warts on the feet while other types can cause warts on the face or neck.

Most HPV infections don’t lead to cancer; however, some types of genital HPV can cause cervical cancer. Vaccines can protect against strains of genital HPV that are more likely to cause genital warts or cervical cancer.



In most cases, the immune system fights off an HPV infection before it causes any warts. On the other hand, when warts appear, their appearance may vary relative to which strain of HPV is involved.


  • Genital warts: They appear as flat lesions, small cauliflower-like bumps or tiny stem-like protrusions. In women, genital warts mainly appear on the vulva but may also appear near the anus, on the cervix or in the vagina. In men, genital warts can appear on the penis and scrotum or around the anus. Genital warts rarely cause pain but they may cause itching.
  • Common warts: Rough, raised bumps that usually appear on the hands, fingers or elbows. Common warts don’t usually cause discomfort but they may be painful or susceptible to injury or bleeding.
  • Plantar warts: Hard, grainy growths that usually appear on the heels or balls of the feet (areas that feel most pressure). They can cause pain and discomfort.
  • Flat warts: Flat-topped, slightly raised lesions darker than the skin color. They usually appear on the face, neck or areas that have been scratched. HPV infections that cause flat warts mostly affect children, adolescents and young adults.



Cervical cancer

Most cases of cervical cancer are caused by two specific strains of genital HPV. The two particular strains usually don’t cause warts so women are often unaware of the infection. Moreover, early stages of cervical cancer typically cause no symptoms. Therefore, it is important for women to have regular Pap tests that can detect any precancerous changes in the cervix.



HPV infection occurs when the virus enters the body through a cut, abrasion or small tear in the outer layer of the skin. The virus is primarily transferred by skin-to-skin contact.

Genital HPV infections are contracted through sexual intercourse, anal sex or other skin-to-skin contact in the genital region. HPV infections that cause oral or upper respiratory lesions are contracted by oral sex.

Another possibility is for an infected mother to transmit the virus to her baby during delivery.


Risk factors

Risk factors for HPV infection include:


  • Number of sexual partners: A large number of sexual partners or multiple sexual partners increases the likelihood of contracting and HPV infection.
  • Age: Common warts occur mostly in children while plantar warts occur in adolescents and young adults but can also occur in adults. Genital warts occur mostly in adolescents and young adults.
  • Weakened immune systems: A weakened immune system is at greater risk of contracting HPV infections. Immune systems can be weakened by HIV/AIDS or by immune system-suppressing drugs.
  • Damaged skin: Punctured or open areas of skin are more susceptible to develop common warts.
  • Personal Contact: Touching someone’s warts or surfaces exposed to HPV without protection can increase the risk of an HPV infection.




Complications of HPV infection include:


  • Oral and upper respiratory lesions (on tongue, tonsils, soft palate, larynx and nose)
  • Cancer (cervical, anal, mouth and upper respiratory cancers)



It is difficult to prevent HPV infections that cause common warts. However, the risk of spreading the infection can be minimized.


Plantar warts

Wearing shoes in public places that attract a large crowd can reduce the risk of contracting HPV infections that cause plantar warts.


Genital warts

Reducing the risk of developing genital warts and other HPV-related genital lesions:


  • Mutually monogamous sexual relationship
  • Reducing the number of sex partners
  • Safe sex (ex. Condoms)


HPV Vaccines

HPV vaccination is available to provide protection of certain strains of HPV. Gardasil vaccine protects against strains of HPV that cause genital warts and cervical cancer while the vaccine Cervarix protects against cervical cancer but not genital warts.

HPV vaccination is most effective on children aged 11 and 12 before they become sexually active. The vaccine can also be administered to people between the ages of 21 and 30.

Side effects from the vaccines include soreness at the injection site, headaches, low-grade fever or flu-like symptoms.