title: Prevalence of human papillomavirus infection in women in Portugal: the CLEOPATRE Portugal study.
abstract: OBJECTIVE
  Human papillomavirus (HPV) is responsible for a range of diseases, including cervical cancer. The primary objectives of the CLEOPATRE Portugal study were to estimate the overall and age-stratified prevalence of cervical HPV infection and to assess HPV prevalence and type-specific distribution by cytological results among women aged 18 to 64 years, who reside in mainland Portugal.
  
  
  METHODS
  This cross-sectional population-based study recruited women aged 18 to 64 years, according to an age-stratified sampling strategy, who attended gynecology/obstetrics or sexually transmitted disease clinics across the 5 regional health administrations in mainland Portugal between 2008 and 2009. Liquid-based cytology samples were collected and analyzed centrally for HPV genotyping (clinical array HPV 2 assay) and cytology. Prevalence estimates were adjusted for age using 2007 Portuguese census data.
  
  
  RESULTS
  A total of 2326 women were included in the study. The overall prevalence of HPV infection in the study was 19.4% (95% confidence interval, 17.8%-21.0%), with the highest prevalence in women aged 18 to 24 years. High-risk HPV types were detected in 76.5% of infections, of which 36.6% involved multiple types. The commonest high-risk type was HPV-16. At least 1 of the HPV types 6/11/16/18 was detected in 32.6% of infections. The HPV prevalence in normal cytology samples was 16.5%. There was a statistically significant association between high-risk infection and cytological abnormalities (P < 0.001).
  
  
  CONCLUSIONS
  This is the first population-based study to quantify and describe cervical HPV infection in mainland Portugal. This study provides baseline data for future assessment of the impact of HPV vaccination programs.
authors.affiliation: National Institute of Health, Lisbon, Portugal. angela.pista@insa.min-saude.pt
authors.forename: Angela
authors.initials: A
authors.lastname: Pista
authors.forename: Carlos Freire
authors.initials: CF
authors.lastname: de Oliveira
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Cunha
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Paixao
authors.forename: Odete
authors.initials: O
authors.lastname: Real
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D027383:Papillomaviridae / Q000145:classification / Q000302:isolation & purification*; D030361:Papillomavirus Infections / Q000453:epidemiology* / Q000821:virology; D011174:Portugal / Q000453:epidemiology; D015995:Prevalence; D002583:Uterine Cervical Neoplasms / Q000453:epidemiology* / Q000821:virology; D055815:Young Adult