title: Epidemiologic profile of type-specific human papillomavirus infection and cervical neoplasia in Guanacaste, Costa Rica.
abstract: BACKGROUND
  Detailed epidemiologic studies of cervical type-specific human papillomavirus (HPV) infection in large populations are scarce.
  
  
  METHODS
  We recruited a population-based cohort in Guanacaste, Costa Rica. Participants were interviewed, screened for cervical neoplasia, and tested for >40 HPV types by use of MY09/11 L1 consensus primer polymerase chain reaction. We estimated the risk factors for infection and the associations between type-specific HPV infections and cervical intraepithelial neoplasia (CIN) and cancer in 8514 sexually active women who had not undergone a hysterectomy.
  
  
  RESULTS
  The overall HPV prevalence was 26.5%. The most common type was HPV-16 (3.6% of the population). HPV prevalence showed a U-shaped age-specific curve. Sexual behaviors were the main determinants of oncogenic and nononcogenic infections; age at first sexual intercourse was not independently associated with infection. Barrier contraceptive use was somewhat protective against infection. Oncogenic infections were strongly associated with risk of all grades of CIN and of cancer. Types 16, 18, and 58 were the most common in women diagnosed with CIN3 and cancer. Except for those that included HPV-16, multiple-type infections were associated with an increased risk (compared with that for single-type infections) of all grades of CIN and of cancer.
  
  
  CONCLUSIONS
  We confirmed the bimodal age pattern of HPV infection in Guanacaste and the sexually transmitted nature of both oncogenic and nononcogenic HPV types.
authors.affiliation: Proyecto Epidemiologico Guanacaste, Fundacion INCIENSA, San Jose, Costa Rica.
authors.forename: Rolando
authors.initials: R
authors.lastname: Herrero
authors.forename: Philip E
authors.initials: PE
authors.lastname: Castle
authors.forename: Mark
authors.initials: M
authors.lastname: Schiffman
authors.forename: M Concepción
authors.initials: MC
authors.lastname: Bratti
authors.forename: Allan
authors.initials: A
authors.lastname: Hildesheim
authors.forename: Jorge
authors.initials: J
authors.lastname: Morales
authors.forename: Mario
authors.initials: M
authors.lastname: Alfaro
authors.forename: Mark E
authors.initials: ME
authors.lastname: Sherman
authors.forename: Sholom
authors.initials: S
authors.lastname: Wacholder
authors.forename: Sabrina
authors.initials: S
authors.lastname: Chen
authors.forename: Ana C
authors.initials: AC
authors.lastname: Rodriguez
authors.forename: Robert D
authors.initials: RD
authors.lastname: Burk
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D003364:Costa Rica / Q000453:epidemiology; D005260:Female; D006801:Humans; D008875:Middle Aged; D027383:Papillomaviridae / Q000145:classification / Q000235:genetics*; D030361:Papillomavirus Infections / Q000150:complications / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D002583:Uterine Cervical Neoplasms / Q000453:epidemiology* / Q000821:virology