Background: Assessment of the prevaccination type-specific prevalence of human papillomavirus (HPV) in the general population is important for the prediction of the impact of HPV vaccination.
Methods: We collected consecutively residual specimens from liquid-based cytology samples from 40,382 women from the general population in Copenhagen, Denmark, during 2002-2005. All samples were tested for high-risk HPV using the Hybrid Capture 2 technique, and genotyping was done using LiPa (Innogenetics). Through linkage with the Pathology Data Bank, we obtained information on the cytology result, and histology if any, on all women.
Results: The participants were 14-95 years of age (median age 37 years) at enrollment. The overall prevalence of HR HPV was 20.6 % ranging from 46.0 % in 20-23-year-old women to 5.7 % in women 65 years or older. Independently of cytology/histology, HPV16 was the most prevalent type. For virtually all HPV types, the occurrence of CIN3+ was higher when the specific HPV type was present together with HPV16 than it was together with other high-risk HPV types than HPV16 or if the HPV type occurred as a single infection. The prevalence of HPV16 and/or HPV18 was 74 % in cervical cancer and the corresponding prevalence of HPV16/18/31/33/45/52/58 was 89 %.
Conclusion: This study forms a valuable starting point for monitoring the effect of HPV vaccination in Denmark. In addition, the particular carcinogenic role of HPV16 and 18 is confirmed and may support a role of genotyping for HPV16 and 18 in cervical cancer screening.