Prevalence of human papillomavirus types 6, 11, 16 and 18 in young Austrian women - baseline data of a phase III vaccine trial

Abstract

Introduction: Cervical cancer is the second most common cancer among women worldwide. In the absence of changing risk or intervention, it is projected that in comparison with 2002 there will be a 40% increase in the number of new cases of cervical cancer by 2020. HPV types 16 and 18 cause 70% of cervical cancers worldwide, 50% of high-grade cervical intraepithelial neoplasias and 25% of low-grade neoplasias. HPV types 6 and 11 are the causative agent of > 90% of genital warts. The aim of this study was to assess the baseline prevalence of infection with HPV 6, 11, 16 and 18 in young Austrian women.

Methods: Austrian females aged 16-24 (n = 123) were enrolled in a double-blind, placebo-controlled, randomized phase III trial of a quadrivalent HPV (types 6, 11, 16, 18) vaccine (FUTURE I, ClinicalTrials.gov number NCT00092521). Healthy women who were not pregnant and had no prior history of genital warts or abnormal results on cervical cytologic testing and had fewer than five lifetime sex partners were eligible for enrollment. The study sub-population was recruited primarily from university settings.

Results: Analysis of the sexual history of the Austrian subjects showed that 92.7% (114/123) were non-virgins and 46.3% were current smokers. At enrollment, 15 (13.5%) had positive serological or PCR tests for HPV 6, 11, 16 or 18. Serologically, 14 (12.3%) of women were positive to HPV 6, 11, 16 or 18: of these, 13 (11.4%) were positive for HPV 16, four (3.5%) were positive for HPV 18, and one (0.9%) for HPV 6. By PCR all were negative for HPV 6 and 11, whereas seven (6.1%) were positive for HPV 16 and one (0.9%) for HPV 18. Abnormal cytology was observed in 12 (10.3%) women.

Discussion: Although the prevalence of vaccine HPV types among young Austrian women with fewer than five lifetime sexual partners was lower than in international data, we observed a high prevalence of abnormal cytology and smoking. These data suggest that a substantial number of Austrian women are at risk for HPV-related disease.