Rapid decline in presentations of genital warts after the implementation of a national quadrivalent human papillomavirus vaccination programme for young women
- 1Melbourne Sexual Health Centre, Alfred Hospital and School of Population Health, University of Melbourne, Carlton, Australia
- 2School of Population Health, University of Melbourne, Carlton, Australia
- 3Centre for Molecular, Environmental, Genetic and Analytic Epidemiology, School of Population Health, University of Melbourne, Carlton, Australia
- 4National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, New South Wales, Australia
- 5Melbourne Sexual Health Centre, Alfred Hospital and Department of Epidemiology and Preventive Medicine, Monash University, Prahran, Victoria, Australia
- Correspondence to Dr C K Fairley, Melbourne Sexual Health Centre, 580 Swanston Street, Carlton, Victoria, Australia, 3053;
- Accepted 10 August 2009
- Published Online First 16 October 2009
Objective: This study aimed to determine if the Australian human papillomavirus (HPV) vaccination programme has had a population impact on presentations of genital warts.
Methods: Retrospective study comparing the proportion of new clients with genital warts attending Melbourne Sexual Health Centre (MSHC) from January 2004 to December 2008. Australia provided free quadrivalent HPV vaccine to 12–18-year-old girls in a school-based programme from April 2007, and to women 26 years and younger through general practices from July 2007.
Results: 36 055 new clients attended MSHC between 2004 and 2008 and genital warts were diagnosed in 3826 (10.6%; 95% CI 10.3 to 10.9). The proportion of women under 28 years with warts diagnosed decreased by 25.1% (95% CI 30.5% to 19.3%) per quarter in 2008. Comparing this to a negligible increase of 1.8% (95% CI 0.2% to 3.4%) per quarter from the start of 2004 to the end of 2007 also in women under 28 years generates strong evidence of a difference in these two trends (p<0.001). There was no evidence of a difference in trend for the quarterly proportions before and after the end of 2007 for any other subgroup, and on only one occasion was there strong evidence of a trend different to zero, for heterosexual men in 2008 in whom the average quarterly change was a decrease of 5% (95% CI 0.5% to 9.4%; p = 0.031).
Conclusions: The data suggest that a rapid and marked reduction in the incidence of genital warts among vaccinated women may be achievable through an HPV vaccination programme targeting women, and supports some benefit being conferred to heterosexual men.
Funding CSB holds a National Medical and Research Council Research Fellowship, grant ID 465164. JSH and LCG hold National Health and Medical Research Council Career Development awards ID 566576 and 454779. No funding was obtained to undertake this study.
Competing interests Declared. CKF owns shares in CSL Biotherapies, the manufacturer of Gardasil. CKF, JSH and BD have received honoraria from CSL Biotherapies. BD has received honoraria from Glaxo SmithKline and BD and CKF have received research funding from CSL Biotherapies. MYC, LCG and CSB have no conflicts of interest.
Ethics approval The study was approved by the Alfred Hospital Ethics Committee as involving “negligible risk” and did not require a formal ethics submission.
Contributors: CKF, JSH, MYC, BD and CSB conceived and designed the study. CKF, JSH and LCG undertook the analysis. All authors critically revised the article for intellectual content and approved the final version. CKF has full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Provenance and Peer review Not commissioned; externally peer reviewed.