Human papillomavirus (HPV)

Human papillomavirus (HPV)Human papillomavirus (HPV) is an extremely common virus. At some point in our life most of us will catch the virus. The world over, HPV is the most widespread sexually transmitted virus; 80% (four out of five) of the world’s population will contract some type of the virus once [1]. If you catch HPV, in the majority of cases the body’s immune system will clear or get rid of the virus without the need for further treatment. In fact you may not even know that you had contracted the virus. 

There are over 100 identified types of HPV; each different type has been assigned a number. HPV infects the skin and mucosa (any moist membranes such as the lining of the mouth and throat, the cervix and the anus). Different types affect different parts of the body causing lesions. The majority of HPV types infect the skin on external areas of the body including the hands and feet. For example, HPV types 1 and 2 cause verrucas on the feet [2].

Around 40 of the HPV types affect the genital areas of men and women, including the skin of the penis, vulva (area outside the vagina), anus, and the linings of the vagina, cervix, and rectum [3]. Around 20 of these types are thought to be associated with the development of cancer. The WHO International Association for Research on Cancer (IARC) identifies 13 of these types as oncogenic (cancer causing). This means there is direct evidence that they are associated with the development of cervical cancer and are considered high-risk [4]. These high risk types of HPV are: 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68 [5]. A person infected with high-risk genital HPV will show no symptoms so they may never even know they have it.

Additionally there are nine HPV types that may also be associated with the development of cervical cancer these are types: 26, 53, 64, 65, 66, 67, 69, 70, 73, 82. However, currently there is not enough evidence to indicate that these types are high risk for cervical cancer [6]. 

The remaining genital HPV types have been designated low-risk as they do not cause cervical cancer but they can cause other problems such as genital warts.


References

  1. Koutsky L. 1997. Epidemiology of genital human papillomavirus infection. The American Journal of Medicine, 102 (5A), 3-8.
  2. Lacey CJ et al., 2006. Chapter 4: Burden and management of non-cancerous HPV-related conditions: HPV-6/11 disease. Vaccine, 24 (3), S3/35-41.
  3. Giuliano AR et al., 2008. Epidemiology of human papillomavirus infection in men, cancers other than cervical and benign conditions. Vaccine, 26 (10), K17-28.
  4. Walboomers JMM et al.,1999 Human papillomavirus is a necessary cause of invasive cancer worldwide. Journal of Pathology, 189 (1), 12–19.
  5. Szarewski A. 2012. Cervarix: a bivalent vaccine against HPV types 16 and 18, with cross-protection against other high-risk HPV types. Expert Review Vaccines 11(6), 645 – 657.
  6. Bouvard et al., 2009. A review of human carcinogens – Part B: biological agents. Lancet Oncology 10, 321 - 322. 
Date last updated: 
30 Apr 2013
Date due for review: 
30 Apr 2015