Objective: To determine in an opportunistic screening programme for Chlamydia trachomatis (CT) the participation and the CT prevalence among the heterosexual population.
Methods: Heterosexually active men and women, 15-40 years old, who consulted a general practitioner in Amsterdam, the Netherlands, in the period May 1996-April 1997, without symptoms of a sexually transmitted disease, were asked after informed consent had been given to provide a first-voided urine sample and a few sociodemographic data. The urine was investigated for CT by means of a ligase chain reaction. In case of a CT infection, the general practitioner was asked for information on treatment and partner notification.
Results: A total of 3689 persons were eligible for the study of whom 214 (5.8%) refused participation. Men refused more often than women (9.0% and 4.3% respectively). No relation was found with ethnic background or health care insurance (national health cost insurance/private medical insurance). Refusers were somewhat younger than participants (not statistically significant). CT was diagnosed in 4.9% (95% confidence interval (95% CI): 4.1-5.9) of the women and in 4.7% (95% CI: 3.6-6.1) of the men. In women a decreasing trend was seen in the prevalence of CT with an increase in age: from 13.4% in the group 15-19 years old to 2.3% in the group 35-40 years old. Independent of age a higher prevalence was found in Surinam Creole women. In 83% of the CT patients the general practitioner spoke with the patient about partner notification; usually there was one partner.
Conclusion: There was a high participation rate (94%) in this opportunistic screening programme in which urine was tested for presence of CT. The CT prevalence in this asymptomatic population was almost 5%, but it was significantly higher in young women and women from Surinam. It is proposed to start such a screening programme in all general practices in Amsterdam.