Decline of the new Swedish variant of Chlamydia trachomatis after introduction of appropriate testing

Sex Transm Infect. 2012 Oct;88(6):451-5. doi: 10.1136/sextrans-2011-050409. Epub 2012 Apr 27.

Abstract

Objective: The longitudinal epidemiological development of the new variant of Chlamydia trachomatis was studied after appropriate testing procedures had been introduced when the strain was detected in 2006.

Methods: The number of cases of the new variant of C trachomatis was followed from 2007 through 2011 from the laboratory records. Testing for C trachomatis is centralised to one laboratory with around 80-85 000 persons being tested annually in a population of 1.1 million.

Results: During the 5-year period, 410 973 patients were tested of which 25 723 cases were positive. The proportion of the new variant of all positive cases declined from 30% in 2007 to 6% in 2011. While the number of the new variant of C trachomatis declined, the ordinary wild-type strains remained largely unchanged.

Conclusions: A selective decline of the new variant of C trachomatis has occurred after appropriate laboratory testing was introduced. A new balance point between 5% and 10% for the new variant seems to be gradually approached.

MeSH terms

  • Adolescent
  • Adult
  • Bacteriological Techniques / methods*
  • Chlamydia trachomatis / classification*
  • Chlamydia trachomatis / isolation & purification*
  • Female
  • Humans
  • Incidence
  • Lymphogranuloma Venereum / diagnosis*
  • Lymphogranuloma Venereum / epidemiology*
  • Male
  • Middle Aged
  • Molecular Diagnostic Techniques / methods*
  • Sweden / epidemiology
  • Young Adult