A retrospective study of recurrent chlamydia infection in men and women: is there a role for targeted screening for those at risk?

Chalmydia trachomatis remains the commonest sexually transmitted infection (STI) in the UK. This study identifies those at risk of recurrent infection (RI) attending a central genitourinary clinic, time to subsequent reinfection and duration of at-risk behaviour for the consideration of targeted chlamydia screening. From 1995 to 2005, a total of 14,011 patients' were diagnosed with chlamydia and 1743 (12.4%) had RI, classified as a repeat infection greater than three months after initial diagnosis. Individual risk factors for both sexes include young age <25, two or more partners and failure to attend for test of cure (TOC) and previous STI. Men of non-White ethnicity, symptoms and those self-referred were also at risk. Combined risk factors for both sexes were non-White ethnicity, symptoms, young age, previous STI and two or more partners. Attendance for TOC considerably reduced RI rates in men (odds ratio [OR] = 0.549; 95% confidence interval [CI] 0.359-0.840). Mean time to first and last reinfection in men was 1.91 and 2.49 years, in women 1.76 and 1.92 years. One in eight individuals with chlamydia infection are at risk of RI, the majority of which will occur within two years of initial presentation. These individuals have identifiable risk factors facilitating targeted re-screening, enhanced follow-up and support for behavioural change.