Australia introduced an HPV vaccination programme, with the quadrivalent HPV vaccine, for all women aged 12–26 years between 2007 and 2009.
Researchers analysed trends in both high-grade and low-grade cervical abnormalities in women in Victoria, Australia, before and after introduction of the vaccination programme.
After the introduction of vaccination, the incidence of high-grade abnormalities in girls aged 17 years and younger fell by 0.38% compared with before the vaccination programme, from 0.80% to 0.42%. But no decline was seen in low-grade abnormalities or in older women.
Dr Julia Brotherton, medical director of the Victorian Cytology Service Registries in Melbourne, concluded: ‘Our finding that the decrease in high-grade abnormalities incidence occurred in the youngest vaccination cohort before it occurred in the older, catch-up cohorts – who were more likely to have been previously sexually experienced – reinforces the appropriateness of the targeting of prophylactic HPV vaccines to preadolescent girls.’