Photo by @NAO<\/a><\/p>\n A vaccination programme against the HPV virus was introduced in England in 2008 for girls aged 12-13 along with catch-up programme<\/a> for those aged 14-18. Many people expected cervical cancer rates in women aged 20-24 to fall by 2014, when the vaccinated cohorts entered their twenties. However, we do not think that is reasonable.<\/p>\n As can be seen in Table 1 below, the first vaccinated women (those aged 17-18 in 2008) would have been invited for screening for the first time in September 2015. Less than 50% of these women received the vaccine.<\/p>\n The HPV vaccine works<\/a> by preventing infection with HPV types 16 and 18. Therefore women already infected by the time they are vaccinated, have little or no benefit of the vaccine. It is estimated that in 2008 between 17% and 20% of women aged 16-18yrs<\/a> in England were infected with the HPV 16\/18 virus. Therefore, at most only 40% of those invited for screening in September 2015 (80% of the 50% vaccinated is 40%) will have benefited from the vaccine. The vaccine should prevent about 70% of cervical cancer (maybe slightly more in young women, particularly, as seems to be the case, if the vaccine has partial protection against other types of the virus). Thus, we might expect to see a fall in cervical cancer in 25 year old women in 2016 of about nearly 30% (70% of 40% is 28%).<\/p>\n It will not be until September 2018 that a substantial proportion of the population coming for screening will have been vaccinated before being exposed to the HPV virus.<\/p>\n