Lymphogranuloma venereum rates increased and Chlamydia trachomatis genotypes changed among men who have sex with men in Sweden 2004-2016.

This study aimed to determine the incidence of lymphogranuloma venereum (LGV) in Sweden since 2004 and to study in detail a consecutive number of Chlamydia trachomatis cases in men who have sex with men (MSM) during a 10 month period (September 2014 to July 2015). LGV increased from sporadic import cases in 2004 to comprise a spread within Sweden in 2016. Initially, only the L2b ompA genotype was detected, but in 2015 half of the genotyped LGV cases were L2 genotype. The changing genotype distribution in Sweden is linked to increased LGV spread in Europe. High-resolution multilocus sequence typing of 168 C. trachomatis cases from MSM in 2015 resulted in 29 sequence types, of which 3 accounted for 49 % of cases. The increased rates and different genotypes of LGV indicate that more concern for high-risk taking MSM is needed to avoid further spread of this invasive infection.