Prevent cervical cancer with HPV vaccines
New evidence published today in the Cochrane Library shows that human papilloma virus (HPV) vaccines protect against cervical lesions in young women, particularly in those who are vaccinated between the ages of 15 and 26. It also summarizes findings on harms that have been assessed in randomized controlled trials.
Most people who have sexual contact at some point in their life will be exposed to the human papilloma virus (HPV). In the majority of women, HPV infection will be cleared by the immune system. When the immune system does not clear the virus, persistent HPV infection can cause abnormal cervical cells. These lesions are known as cervical 'precancer' because over time they can progress to cervical cancer if left untreated.
There are many different types of HPV. Some are associated with the development of cervical lesions that can become cancerous and are considered as high-risk HPV types. Two of these high-risk types (HPV16 and HPV18) account for about 70% all cases of cervical cancer worldwide. Vaccines have been developed that help the immune system to recognize certain HPV types. Because cervical cancer can take several years to develop, regulatory bodies and international health agencies such as the World Health Organization (WHO) regard cervical lesions as the preferred outcome measure for HPV vaccine trials.