title: Prevalence of human papillomavirus in young Italian women with normal cytology: how should we adapt the national vaccination policy?
abstract: BACKGROUND
  Human Papillomavirus (HPV) is the most common sexually transmitted infection. In Italy, HPV vaccination is now offered free of charge to 12-year-old females. However, some regional health authorities have extended free vaccination to other age-groups, especially to girls under 18 years of age. We conducted a multicentre epidemiological study to ascertain the prevalence of different genotypes of HPV in young Italian women with normal cytology, with the aim of evaluating the possibility of extending vaccination to older females.
  
  
  METHODS
  The study was performed in 2010. Women aged 16-26 years with normal cytology were studied. Cervical samples were analyzed to identify the presence of HPV by PCR amplification of a segment of ORF L1 (450 bp). All positive HPV-DNA samples underwent viral genotype analysis by means of a restriction fragment length polymorphism assay.
  
  
  RESULTS
  Positivity for at least one HPV genotype was found in 18.2% of the 566 women recruited: 48.1% in the 16-17 age-class, 15.4 in the 18-20 age-class, 21.9% in the 21-23 age-class, and 15.5% in the 24-26 age-class; 10.1% of women were infected by at least one high-risk HPV genotype. HPV-16 was the most prevalent genotype. Only 4 (0.7%), 4 (0.7%) and 3 (0.5%) women were infected by HPV-18, HPV-6 and HPV-11, respectively. Of the HPV-DNA-positive women, 64.1% presented only one viral genotype, while 24.3% had multiple infections. The HPV genotypes most often involved in multiple infections were high-risk. A high prevalence was noted in the first years of sexual activity (48.1% of HPV-DNA-positive women aged 16-17 years); HPV prevalence subsequently declined and stabilized.The estimate of cumulative proportions of young women free from any HPV infection at each age was evaluated; 93.3% and 97.1% of 26 year-old women proved free from HPV-16 and/or HPV-18 and from HPV-6 and/or HPV-11, respectively.
  
  
  CONCLUSIONS
  Our findings confirm the crucial importance of conducting studies on women without cytological damage, in order to optimise and up-date preventive interventions against HPV infection, and suggest that vaccinating 26-year-old females at the time of their first pap-test is to be recommend, though this issue should be further explored.
authors: Department of Health Sciences, Genoa University, Via Pastore, 1, Genoa 16132, Italy. panatto@unige.it.
authors: Donatella
authors: D
authors: Panatto
authors: Daniela
authors: D
authors: Amicizia
authors: Elisabetta
authors: E
authors: Tanzi
authors: Silvia
authors: S
authors: Bianchi
authors: Elena Rosanna
authors: ER
authors: Frati
authors: Carla Maria
authors: CM
authors: Zotti
authors: Piero Luigi
authors: PL
authors: Lai
authors: Angela
authors: A
authors: Bechini
authors: Stefania
authors: S
authors: Rossi
authors: Roberto
authors: R
authors: Gasparini
mesh_terms: D000293:Adolescent; D000328:Adult; D052685:Alphapapillomavirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D002584:Cervix Uteri / Q000737:chemistry / Q000166:cytology / Q000473:pathology / Q000821:virology*; D004279:DNA, Viral / Q000235:genetics; D005260:Female; D005838:Genotype; D006291:Health Policy; D006801:Humans; D007558:Italy / Q000453:epidemiology; D030361:Papillomavirus Infections / Q000453:epidemiology* / Q000517:prevention & control / Q000821:virology*; D053918:Papillomavirus Vaccines / Q000008:administration & dosage; D015995:Prevalence; D002583:Uterine Cervical Neoplasms / Q000453:epidemiology / Q000235:genetics / Q000517:prevention & control; D014611:Vaccination; D014626:Vaginal Smears; D055815:Young Adult
chemical_list: D004279:DNA, Viral; D053918:Papillomavirus Vaccines