HPV vaccine ‘effective’

The HPV vaccination programme successfully protects young women against cervical abnormalities, according to a new study published today.

A team of researchers from Queensland, Australia, set out to measure the effectiveness of the quadrivalent human papillomavirus (HPV) vaccine against cervical abnormalities four years after a national vaccination programme began. The quadrivalent vaccine is one of the two HPV vaccines currently available worldwide. It is targeted against HPV types 6, 11, 16, and 18. The other is the bivalent vaccine, targeted against types 16 and 18.

The researchers used figures on all female Queensland residents attending their first cervical smear test. Among these were 1,062 women with confirmed high grade cervical abnormalities, 10,887 with other abnormalities, and 96,404 with normal smear results.

Those with high grade cervical abnormalities were older, more disadvantaged and less likely to live in major cities. Fewer of these women (11%) were fully vaccinated than those who had less dangerous abnormalities (19%) or had healthy results (24%).

The full three doses of the vaccine are estimated to provide 46% protection against high grade cervical abnormalities and 34% protection against other cervical abnormalities. Two doses of the vaccine provided 21% protection against both high grade and other cervical abnormalities, but no significant protection was seen with just one dose.

Writing in today’s (5 March) British Medical Journal, Professor David Whiteman and colleagues conclude: "The quadrivalent HPV vaccine conferred statistically significant protection against cervical abnormalities in young women.

"Continued observation of this population is necessary to assess the implications for cervical screening recommendations in the coming era of mass vaccination."

Crowe, E. et al. Effectiveness of quadrivalent human papillomavirus vaccine for the prevention of cervical abnormalities: a case-control study nested within a population-based screening program in Australia. BMJ 5 March 2014 doi: 10.1136/bmj.g1458 [abstract]