Prevalence trends of the new variant of Chlamydia trachomatis in four counties of Sweden in 2007-2011.

A new variant of Chlamydia trachomatis (nvCT) was discovered in Sweden in 2006, and it could not be detected by diagnostic systems from Abbott and Roche, whereas the third system used, from Becton Dickinson (BD), detects nvCT. We analyzed 3648 samples from 2 counties that used Roche and 2 counties that used BD methods from 2007 to 2011. After implementation of a Roche method that detects nvCT, its proportion has decreased and converged in the 4 counties but are still at different levels in Roche and BD counties. Future studies are needed to see if nvCT will decline further.