human papillomavirus
Meaning of human papillomavirus: Infection is close to universal and usually clears unnoticed, and it is the small share that persists which carries any cancer risk.
Definition of human papillomavirus
Human papillomavirus is a large family of viruses that infect skin and the moist linings of the body. More than two hundred types are known. Some cause ordinary warts on the hands and feet, some cause genital warts, and a smaller group can lead to cancer if the infection persists for many years.
What do the different types do?
Describing HPV as a single sexually transmitted infection is too narrow. The family splits into groups that behave quite differently.
| Group | Where it infects | What it causes |
|---|---|---|
| Skin types | Ordinary skin, spread by everyday contact | Common warts on hands, plantar warts on the soles |
| Low-risk mucosal types | Genital and oral linings, spread by skin to skin sexual contact | Genital warts; rarely, growths in the airway |
| High-risk mucosal types | The same linings | No symptoms at the time, but persistent infection can lead to cancer of the cervix, vagina, vulva, penis, anus and the back of the throat |
Most people acquire one or more mucosal types after becoming sexually active, and in the great majority the immune system clears the virus within a couple of years without anything ever being noticed.
How does a lasting infection lead to cancer?
High-risk types make two proteins that interfere with the cell's own safety controls: one disables the protein that halts a damaged cell and triggers its destruction, the other releases the brake on cell division. A cell carrying both keeps dividing and accumulates genetic errors it would normally have been stopped for. This takes years and produces recognizable intermediate stages, in which the lining looks increasingly abnormal but the cells have not yet broken through the boundary beneath. That slow, visible progression is what makes screening possible at all, and it is why cervical cancer is one of the few cancers that can be caught reliably before it exists.
How is it found and prevented?
Because infection produces no symptoms, detection relies on testing rather than on how a person feels. A human papillomavirus DNA test looks for the genetic material of high-risk types, and cell samples from the cervix are examined for the changes those types produce; the two are often done on the same sample. Prevention rests on the human papillomavirus vaccine, which covers the types responsible for most HPV related cancers. Condoms reduce transmission without eliminating it, since the virus spreads by contact with skin the condom does not cover.
Also known as
Used in a sentence
Cervical cytology and HPV testing were performed together as part of the patient's screening visit.
Good to know
Most HPV infections are cleared by the immune system without causing symptoms, and it is persistent infection with certain high-risk types, rather than infection itself, that is linked to cancer development.
Word origin
Where “human papillomavirus” comes from
Formed from papilloma, from Latin papilla, meaning nipple or small projection, and Greek -oma, meaning swelling or tumor, referring to the wart-like growths some types produce, combined with virus, from Latin virus, meaning poison.