Human papillomavirus (HPV)
What is HPV?
HPV stands for human papillomavirus.
HPV is a common sexually transmitted infection which usually shows no symptoms and goes away by itself, but can sometimes cause serious illness.
HPV is responsible for:
- almost all cases of cervical cancer
- 90% of anal cancers
- 78% of vaginal cancers
- 25% of vulva cancers
- 50% of penile cancers
- 60% of oropharyngeal cancers (cancers of the back of the throat, including the base of the tongue and tonsils)
- around 90% of genital warts.
How is HPV transmitted?
HPV can infect both men and women. The virus is spread through intimate contact with genital-skin during sexual activity, via tiny breaks in the skin. Usually this happens without anyone ever knowing it or it causing any problems.
Condoms offer some but not total protection from HPV, as they don’t cover all of the genital skin. They do offer protection from many other sexually transmitted infections though, and help prevent unwanted pregnancy.
You can be exposed to HPV the first time sexual activity occurs, from only one sexual partner.
How common is HPV?
Four out of five people have at least one type of HPV at some time in their lives. It is sometimes called the ‘common cold’ of sexual activity. HPV infects both men and women.
There is currently no treatment for HPV.
In most cases the immune system clears HPV from the body naturally over time and it has no long-lasting effects.
Most people with HPV have no symptoms and will never know they have it. For women, having regular Cervical Screening Testsfrom age 25 is the only way to detect HPV. The HPV vaccine does not protect against all strains of HPV, so it’s important to have regular cervical screening tests whether you are vaccinated or not.
Genital warts can be treated by doctors or at sexual health clinics.
HPV and cancer
There are different HPV types – some are considered “low-risk” and others “high-risk”, based on whether or not they can cause cancer. Low-risk HPV types do not cause cancer, but can cause genital warts. High-risk HPV types can cause cancer, if they persist for a very long time.
In most cases, the immune system clears HPV from the body. However, there are times when the body does not clear HPV: usually when the infection is with high-risk types. We call this ‘persistent’ HPV infection.
Persistent HPV infection can cause abnormal cells to develop on the cervix which may eventually develop into cervical cancer if left untreated. Cervical cancer is the most common type of cancer caused by HPV, but persistent infection also causes less common cancers affecting men and women, including anal, vulvar, vaginal, mouth/throat and penile cancers. It takes a very long time between becoming infected with HPV and developing cancer.
HPV can be prevented through vaccination. The first HPV vaccines protected against two high risk types (16 and 18), that cause about 70% of cervical cancers and 77% of the other HPV-related cancers in women and men.
The HPV vaccine that’s now the most commonly used in Australia – Gardasil 9 – protects against seven high-risk HPV types (types 16, 18, 31, 33, 45, 52 and 58), which cause 90% of cervical cancers in women and around 90% of other HPV-related cancers in women and men. It also protects against two non-cancerous types (types 6 and 11), which cause 90% of genital warts.
All boys and girls aged 12-13 should have the HPV vaccine. The vaccine is most effective if given before exposure to HPV that is before sexual activity commences.
Gardasil 9 is available free of charge through the school-based National HPV Vaccination Program and involves injections in the upper arm. Those who receive their first dose before age 15 only require two doses, with the second dose given around six months after the first. For those who receive their first dose after they’ve turned 15, the vaccine works best when three doses are given, with the second dose of the vaccine two months after the first, and the third dose four months after the second (at 0, 2 and 6 months).