Re: The remarkable impact of bivalent HPV vaccine in Scotland
This epidemiology report was purely a paper exercise.(1) There were no face to face consultations with any of the screened women. It was interesting to note the authors were claiming herd immunity, for the convergence of both vaccinated and unvaccinated women in the graphical representation, showing a significant reduction in serious cervical lesions in the 20 year old women screened, between birth cohorts 1988 to 1996, (see figures 2 and 3). I am assuming David Thomas’s response is ‘tongue in cheek’ but he has a point. In Scotland, boys, who make up 50% of the ‘herd’, are not being HPV vaccinated until later this year in Scotland. The top two graphs in Figure 2 also demonstrated for the incidence of minor lesions ASCUS and LSIL the vaccine has made almost no difference during the time period studied.
I would assume those schoolgirls would have received some counselling with their vaccines, particularly on the subject of safe sex and how HPV infection could be avoided. These lessons would be taught to both boys and girls, vaccinated and unvaccinated, and could very possibly account for the reduction in serious lesions reported for the 20 year old women screened. I was very concerned the authors deliberately discounted the data recorded for women who had received only one or two HPV vaccine doses, (see Top Table 3). For the vaccine to be proven effective, there should have been a significant reduction in cervical lesions in the women screened, but the data records little or no improvement in the overall figures. The authors claim the numbers are too small (6186) for an accurate assessment to be made, yet they include in their assessments the data for the relatively small numbers of women unvaccinated in Table 4, (2210, ages 12-13), (5472, ages 14-15), and (7896, ages 16-17).
Interestingly, there were no CIN Grade 3 lesions recorded for the unvaccinated 12-13 ages cohort, which rather backs up my point about school HPV counselling. The older unvaccinated and vaccinated age cohorts will have missed out on this essential information.
1. Prevalence of cervical disease at age 20 after immunisation with bivalent HPV vaccine at age 12-13 in Scotland: retrospective population study Tim Palmer,1 Lynn Wallace,2 Kevin G Pollock,3,4 Kate Cuschieri,5 Chris Robertson,3,6,7 Kim Kavanagh,7 Margaret Cruickshank
Competing interests: No competing interests