infection is uncommon in the British general population: implications for clinical testing and public health screening.

Introduction: Variable use of new molecular assays, asymptomatic infections and a lack of population data mean that the population burden of is uncertain. We investigated the age-specific prevalence of within the sexually active British general population to inform testing strategies.

Methods: Britain's third National Survey of Sexual Attitudes and Lifestyle (Natsal-3) is a probability sample survey of 15 162 individuals aged 16-74 years, undertaken during 2010-2012. Urine from 4386 participants aged 16-44 years reporting ≥1 lifetime sexual partner was tested for using in-house real-time PCR.

Results: Urinary was detected in seven women and no men providing urine samples, giving a weighted prevalence estimate of 0.3% (95% CI 0.1% to 0.5%) in sexually experienced women aged 16-44 years. Of the seven women with detected, four were of black or mixed ethnicity (prevalence 2.7% (0.9% to 7.7%) in this group) and five reported recent partners of black or mixed ethnicity. Six of the women reported symptoms, and five reported sexual health clinic attendance in the past 5 years (prevalence in those reporting clinic attendance: 1.0% (0.4% to 2.3%)). The prevalence of a self-reported history of (past 5 years) was 0.1% (0.0% to 0.2%) in women and 0.0% (0.0% to 0.2%) in men aged 16-44 years.

Conclusions: Our British population prevalence estimates indicate that is a rare infection. These data support policies that restrict asymptomatic screening for and suggest deployment of molecular tests should be focused within clinical settings and guided by symptoms and local demography.