Minimum spread of the new Swedish variant of Chlamydia trachomatis and distribution of C. trachomatis ompA genotypes in three geographically distant areas of Spain, 2011-2012.

Purpose: The aim of this study was to determine the presence of the new Swedish Chlamydia trachomatis (C. trachomatis) variant (nvCT) and the distribution of C. trachomatis ompA genotypes in three geographically distant regions of Spain.

Methods: The genotypes of strains causing 624 episodes of infection (January 2011-September 2012) were studied using a nested PCR that amplifies a fragment of the ompA gene, followed by sequencing. To detect nvCT, a real-time PCR was used that amplifies a fragment of the cryptic plasmid with a 377 base pair deletion, which identifies the nvCT.

Results And Conclusion: The ompA genotype was identified in 565 (90.5%) episodes. Eleven genotypes were detected, of which nine were found in all three regions. Only one nvCT strain was detected (0.4%), despite the predominance of genotype E (41%). Other frequent genotypes were genotypes D (19%), F (13%), G (11 %), and J (7%). Genotype L2b, causing lymphogranuloma venereum, was detected in men who have sex with men (MSM) in all three regions. Genotypes E and F were more frequent in women and heterosexual men, and genotypes D, G, J and L2b in MSM. In men, the main factor causing differences in the distribution of C. trachomatis was sexual behavior (MSM versus heterosexual men), while the distribution of C. trachomatis genotypes was similar in women and heterosexual men.