title: Age-specific prevalence of infection with human papillomavirus in females: a global review.
abstract: OBJECTIVE
  Global data on age-specific prevalence of human papillomavirus (HPV) infection overall, and for high-risk HPV types 16 and 18, are essential for the future implementation of HPV prophylactic vaccines for cervical cancer prevention.
  
  
  METHODS
  A systematic review of peer-reviewed publications was conducted to summarize worldwide data on genital HPV-DNA prevalence in women. Studies with clear descriptions of polymerase chain reaction or hybrid capture detection assays were included.
  
  
  RESULTS
  A total of 346,160 women were included in 375 studies. Of 134 studies with age-stratified HPV prevalence data (116 low sexual risk populations, 18 high sexual risk populations), over 50% were from Europe and the Middle East (38%) and North America (19%), with smaller proportions from Asia and Australia (21%), Central and South America (11%), and Africa (10%). Across all geographical regions, data on HPV prevalence were generally limited to women over 18 years of age. Consistently across studies, HPV infection prevalence decreased with increasing age from a peak prevalence in younger women (< or =25 years of age). In middle-aged women (35-50 years), maximum HPV prevalence differed across geographical regions: Africa (approximately 20%), Asia/Australia (approximately 15%), Central and South America (approximately 20%), North America (approximately 20%), Southern Europe/Middle East (approximately 15%), and Northern Europe (approximately 15%). Inconsistent trends in HPV prevalence by age were noted in older women, with a decrease or plateau of HPV prevalence in older ages in most studies, whereas others showed an increase of HPV prevalence in older ages. Similar trends of HPV 16 and/or 18 prevalence by age were noted among 12 populations with available data.
  
  
  CONCLUSIONS
  Genital HPV infection in women is predominantly acquired in adolescence, and peak prevalence in middle-aged women appears to differ across geographical regions. Worldwide variations in HPV prevalence across age appear to largely reflect differences in sexual behavior across geographical regions. Further studies of HPV prevalence in adolescents are needed for all geographic regions.
authors.affiliation: Department of Epidemiology, University of North Carolina, Chapel Hill, North Carolina 27599, USA. jennifers@unc.edu
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Smith
authors.forename: Amy
authors.initials: A
authors.lastname: Melendy
authors.forename: Rashida K
authors.initials: RK
authors.lastname: Rana
authors.forename: Jeanne M
authors.initials: JM
authors.lastname: Pimenta
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D052162:Human papillomavirus 16 / Q000235:genetics / Q000302:isolation & purification; D052161:Human papillomavirus 18 / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D008875:Middle Aged; D030361:Papillomavirus Infections / Q000453:epidemiology*; D015995:Prevalence; D002583:Uterine Cervical Neoplasms / Q000453:epidemiology* / Q000821:virology; D016387:Women's Health
chemical_list: D004279:DNA, Viral