Prevalence of human papillomavirus infection in women in Turin, Italy.

Human papillomavirus (HPV) is recognised as necessary for the development of cervical cancer. An age-stratified random sample of 1013 women, aged 25-70 years, participating in the organised cervical screening programme in Turin, Italy was tested for 36 HPV types using polymerase chain reaction (PCR) with the general primers GP5+/GP6+. The overall HPV prevalence was 8.8%. High-risk types were found in 7.1% of women and multiple infections in 1.1%. HPV-16 was the most common type (32.6% of HPV-positive women). HPV prevalence (any type) was 13-14% at ages 25-39 years, 11.5% at age 40-44 years, and approximately 5% among older women. After age-adjustment, HPV prevalence was significantly increased in single vs married, (Odds Ratio (OR)=2.23; 95% Confidence Interval (CI): 1.28-3.89) and decreased in parous vs nulliparous women (OR=0.49; 95% CI: 0.31-0.78). However, the association with marital status and parity was restricted to women less than 45 years of age. In conclusion, overall, the female population of Turin showed an HPV prevalence that is intermediate compared with worldwide levels.