Background: The national human papillomavirus (HPV) immunization program was introduced in England in September 2008 using the bivalent vaccine.
Methods: We collected residual vulva-vaginal swab specimens from 16 to 24-year-old women attending for chlamydia screening between 2010 and 2016 and tested for HPV DNA. We compared changes in type-specific (vaccine and nonvaccine) HPV prevalence over time and association with vaccination coverage. For women with known vaccination status, vaccine effectiveness was estimated.
Results: HPV DNA testing was completed for 15459 specimens. Prevalence of HPV16/18 decreased between 2010/2011 and 2016 from 8.2% to 1.6% in 16-18 year olds and from 14.0% to 1.6% in 19-21 year olds. Declines were also seen for HPV31/33/45 (6.5% to 0.6% for 16-18 year olds and 8.6% to 2.6% for 19-21 year olds). Vaccine effectiveness for HPV16/18 was 82.0% (95% confidence interval [CI], 60.6%-91.8%) and for HPV31/33/45 was 48.7% (95% CI, 20.8%-66.8%). Prevalence of HPV16/18 was compared to findings in 2007-2008 (prevaccination) and to predictions from Public Health England's mathematical model.
Discussion: Eight years after the introduction of a national HPV vaccination program, substantial declines have occurred in HPV16/18 and HPV31/33/45. The prevalence of other high-risk HPV types has not changed.