title: Chlamydia trachomatis prevalence and sexual behaviour in Christchurch high school students.
abstract: OBJECTIVE
  To estimate the prevalence of Chlamydia trachomatis among young people in Year 12 and Year 13 in Christchurch secondary schools.
  
  
  METHODS
  A cross-sectional survey on sexual behaviour was carried out in conjunction with the collection of urine samples, which were tested for C. trachomatis.
  
  
  RESULTS
  1582 young people were invited to take part in the study. 72% of these students answered the questionnaire of whom 49% had experienced sexual intercourse. The mean age of the sample was 16.7 years. The prevalence of C. trachomatis among the sexually active participants who provided a urine sample was 2.0% (1.8% of males and 2.3% of females). 39% of sexually active participants had had one partner in their lifetime and 13% had had more than five partners. 51% of males and 39% of females indicated that they always used condoms and 69% of males and 57% of females reported using a condom on the last occasion of sexual intercourse.
  
  
  CONCLUSIONS
  Our study shows that 2.0% of sexually active senior high school students have asymptomatic C. trachomatis infections. Opportunistic screening for C. trachomatis should be offered to all sexually active males and females at risk.
mesh_terms: D000293:Adolescent; D000328:Adult; D002690:Chlamydia Infections / Q000453:epidemiology* / Q000208:ethnology; D002692:Chlamydia trachomatis / Q000302:isolation & purification; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D015995:Prevalence; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D012749:Sexually Transmitted Diseases / Q000453:epidemiology; D011795:Surveys and Questionnaires; D014556:Urine / Q000382:microbiology