Prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae infection in adolescents in Northern Italy: an observational school-based study

BACKGROUND

We carried out a study to evaluate the prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae genital infections in school-based adolescents in Northern Italy.

METHODS

Systematic screening for C. trachomatis and N. gonorrhoeae genital infection was performed in 13th grade students in the province of Brescia, an industrialized area in Northern Italy. Student filled in a questionnaire on sexual behaviour and provided a urine sample for microbiological testing.

RESULTS

A total of 2,718 students (mean age: 18.4 years; 59.1% females) provided complete data (62.2% of those eligible). Overall 2,059 students (75.8%) were sexually active (i.e. had had at least one partner), and the mean age at sexual debut was 16.1 years (SD: 1.4). Only 27.5% of the sexually active students reported regular condom use during the previous 6 months, with higher frequency in males than in females (33.8% vs 24.2%). No case of N. gonorrhoeae infection was detected, while C. trachomatis was found in 36 adolescents, with a prevalence of 1.7% (95% CI: 1.2-2.4) among sexually active students, and no statistical difference between females and males (1.9 and 1.4%, respectively). Inconsistent condom use (odds ratio, OR = 5.5) and having had more than one sexual partner during the previous 6 months (OR = 6.8) were associated with an increased risk of Chlamydia infection at multivariate analysis.

CONCLUSION

The prevalence of C. trachomatis infection among sexually active adolescents in Northern Italy was low, despite a high proportion of students who engage in risky sexual behaviour. No cases of N. gonorrhoeae infection were identified.