Human papillomavirus (HPV) is a family of viruses which cause a range of serious diseases including cervical cancer and mouth cancer. There are more than 40 types of HPV. Some of the strains also cause genital warts. Before vaccination started in 2009, HPV was the most common sexually transmitted infection (STI) in the UK.
In the UK in 2015, there were 3126 new cases of cervical cancer. In 2016, 854 women in the UK died from cervical cancer (see Cancer Research UK's cervical cancer statistics ). Cervical cancer is the most common cancer among women who are 15 to 34 years old. Unlike the majority of cancers, it is mainly a disease of the young, with 62% of cases occurring in women who are less than 50 years old.
Cervical cancer is also a major issue worldwide. In 2012 there were an estimated 266,000 deaths from cervical cancer (about one every two minutes), and 87% of these occurred in less developed regions of the world.
In most cases HPV infection does not lead to any health problems, and the infection clears by itself. However, in some cases HPV infection can cause cells to become abnormal. The diseases that result from these cell changes often do not show any symptoms until they are quite far advanced. Genital warts can take months to appear after getting HPV, and cancer often takes many years to develop after a person gets HPV.
Over 99% of cervical cancers are caused by HPV infection. Two high-risk types, HPV 16 and HPV 18, are responsible for nearly 75% of all cervical cancers in Europe. Cervical cancer kills around 900 women every year in the UK. HPV types 6 and 11 are responsible for around 90% of the cases of genital warts. Less commonly, HPV can cause anal, oral, and genital cancers in men and women. Different types of HPV cause verrucas and common warts on the skin.
HPV is a sexually transmitted infection (STI). It is passed on through sexual contact (most often intercourse) with an infected person. People can carry and pass on the virus without showing any symptoms themselves. Before a vaccine was introduced, 40% of women aged 20 to 24 years carried types of the virus which cause cancer.
In the UK, the universal HPV vaccine programme has been offered to all 12-13 year old girls since 2008, and from September 2019 the programme will be extended to boys aged 12-13 years. This follows updated evidence from the Joint Committee on Vaccination and Immunisation (JCVI) , the body that advises the Department of Health in the UK. In their updated statement the JCVI advised that the existing HPV vaccination programme for girls should be extended to boys as well. Since April 2018, the vaccine has also been offered to men under the age of 45 who have sex with men.
The actual impact on cervical cancer cases will not be known for certain until the first cohort of girls who received the HPV vaccine become old enough to develop cervical cancer. However, trials of the vaccine showed it stopped the early pre-cancerous stages, which suggests that it could have a big impact on cervical cancer cases. The vaccine protects against the two types of HPV (HPV 16 and HPV 18) which cause most cases of cervical cancer. Recent data shows that there has been a significant fall in HPV infections in young women since the vaccine was introduced (see 'More information' below).
Carron’s story – cervical cancer and the HPV vaccine
In this short film, Carron Hulme talks about her experience of surviving cervical cancer, and her daughters Charlotte and Mollie talk about the HPV vaccine. Thanks to Jo’s Cervical Cancer Trust for their help in making this film.
A 2015 report from Public Health England shows a significant fall in HPV infections in young women since the vaccine was introduced. In 2010-13, HPV types 16 and 18 were 66% less common in sexually active young women aged 16-18 than they were in 2008. These early findings support the view that the HPV vaccination programme will have an impact on the numbers of cases of cervical cancer in future.
In Australia, data from sexual health clinics show that cases of genital warts in younger women have fallen since vaccination was introduced. In 2007, the year HPV vaccination started, over 11% of women under 21 were diagnosed with genital warts at their first visit to a clinic. By 2014 this figure had fallen to just over 1%. There was also a decline in cases among 21-30 year old women; some of these would have been vaccinated against HPV. In the older age group (over 30 years) who did not receive HPV vaccination, there was no change between 2007 and 2014.
Source: HIV, viral hepatitis and sexually transmissible infections in Australia Annual Surveillance Report 2015 - The Kirby Institute