Each year in the UK, over 3000 women are diagnosed with cervical cancer and around 300,000 women are told they may have some form of cervical abnormality. Cervical cancer is caused by a very common virus called human papillomavirus (HPV). Anyone who is sexually active can contract HPV through contact with someone who already has the virus. Most people are infected with HPV at some point in their lives but may never know they have been infected. Like other viral infections such as a cold, HPV is usually cleared by the body's immune system without the need for other treatment. We do not know why a small percentage of people do not clear the infection, which can remain 'dormant' (inactive) in their bodies sometimes for many years  .
There are around 13 high-risk types of HPV that are responsible for almost all cervical cancers . Within the high-risk group, types 16 and 18 are the most prevalent and responsible for 70% of cervical cancers . HPV infection can cause changes to the cells of the cervix creating abnormalities. Once these abnormalities become severe they can develop into cancer which is why cervical screening and HPV vaccination are important in helping to prevent cervical cancer.
There are two HPV vaccines which provide protection against the two high risk types of HPV (types 16 and 18) that cause 70% of all cervical cancers. One of the vaccines is also designed to provide protection against genital warts which are caused by low risk types of HPV. Low risk types of HPV do not cause cervical cancer.
Research indicates that the HPV vaccine could prevent two thirds of cervical cancers in women under the age of 30 by 2025 but only if uptake of the HPV vaccination is at 80% . To date, the UK has achieved this level each year in the national HPV immunisation programme.
- Muñoz N, et al., 2009. Persistence of HPV infection and risk of high-grade cervical intraepithelial neoplasia in a cohort of Colombian women. British Journal of Cancer 100, 1184–1190.
- Moscicki, AB, et al., 1998. The natural history of human papillomavirus infection as measured by repeat DNA testing in adolescent and young women. Journal of Pediatr 132, 277-284.
- Li N et al., 2011. Human papillomavirus type distribution in 30,848 invasive cervical cancers worldwide: variation by geographical region, histological type and year of publication. International Journal of Cancer 128, 927–935.
- Bosch, F.X., et al., Epidemiology and natural history of human papillomavirus infections and type-specific implications in cervical neoplasia. Vaccine, 2008. 26 (10), K1-16.
- Cuzick J, Castanon A, and Sasieni P. 2010. Predicted impact of vaccination against human papillomavirus 16/18 on cancer incidence and cervical abnormalities in women aged 20–29 in the UK. British Journal of Cancer 102, 933-939.
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