Epidemiology and genotype distribution of human papillomavirus (HPV) in women of Sardinia (Italy)

The human papillomavirus (HPV) infection is necessary for the development of cervical cancer. Our study aims to evaluate the rate of HPV circulation in our population, to identify the prevalent genotypes and to establish correlation with cervical abnormalities. Furthermore, the awareness of women about HPV issues was investigated.This study included 864 women attending the Oncologic Prevention Service for their routine Pap test screening or the Health Promotion Mother-Child Service for counselling about sexual activity, from July 2006 to September 2007. All the participants gave their informed consent to be enrolled in the study and were invited to fill in a questionnaire about the socio-cultural state, sexual activity and awareness about HPV. The women samples were tested for HPV-DNA and HPV genotypes: any type of HPV-DNA was detected in 31.0% of the women; single or multiple infections sustained by HPV-16 or HPV-18 represented 43.5% of all HPV infections, accounting for infections in 11.8% of the recruited women. The HPV and high-risk HPV (HR-HPV) prevalence significantly declined in women older than 46 years. The Pap test result was available in 490 women; 48.1% of the Pap test positive women had also an HPV infection and among these 22.7% were infected by HPV-16 and/or HPV-18 genotype, while 51.9% (94/181) were HPV negative. The analysis by binary logistic regression showed that genotype 16 and/or 18 is a risk factor for the Pap positive test with a odds ratio (OR) of 2.9 (95% C.I. 1.4–5.9) and 3.6 (95% C.I. 1.58–8.42) respectively, while age is a protective factor (OR 0.97, C.I. 95% 0.96–0.99); furthermore, the mean age at the first sexual intercourse and the mean number of partners since the beginning of sexual activity, were statistically associated with the risk of HPV infection. More than half of women were aware about HPV, its sexual transmission and of its correlation with cervix cancer.Our findings evidenced that HPV infection is frequent in women aged 18–46 years in Sardinia and particularly that 16 and 18 HPV genotypes are detectable in more than 40% of the infected women. The proportion of women informed about HPV issues is sufficient to guarantee an aware approach to HPV vaccination.