Abstract
OBJECTIVES: The discovery of a variant strain of Chlamydia trachomatis (Ct) in Sweden has raised awareness of its possible undetected spread in the UK. The assays that fail to detect this variant are widely used in this country. This study aimed to determine if this variant is circulating in the UK. METHOD: 1,680 genital specimens tested negative by the Roche assays were retested by Aptima Combo2. Discordant results were sequenced to check for the deletion variant. RESULTS: Of 1,680 specimens tested, 29 were candidates for sequencing: 16 were negative for the variant, 11 failed to amplify, and 2 were lost. DISCUSSION: No Ct deletion variants were found in the UK. If it is circulating, then the prevalence is low (0-0.77%), but even a low level cannot be ignored. The system we describe is simple and suitable for rapid response and phasing of surveillance to match an unknown level of threat if other variants emerge.