Longitudinal assessment of infecting serovars of Chlamydia trachomatis in Seattle public health clinics: 1988-1996

Sex Transm Dis. 2003 Apr;30(4):357-61. doi: 10.1097/00007435-200304000-00016.


Background: There have been few longitudinal studies of fluctuations in the prevalence of Chlamydia trachomatis serovars in a given community; such studies could improve our understanding of the epidemiology and transmission of C trachomatis.

Study design: This was a longitudinal study of 7110 female patients (62%) and 4344 male patients (38%) presenting with first-time infections to health department clinics between 1988 and 1996.

Goal: The goal was to ascertain trends in the proportion of infecting serovars over the 9-year study period and determine independent relationships between serovar and age, gender, race, and year of infection.

Results: Serovar E was the most prevalent (32%), followed by F (18%) and D (13%). Being female, African American, and infected with serovar B was associated with young age (P < 0.001, P < 0.001, and P = 0.09, respectively). Class C serovars were found in older patients (P < 0.001). Over the 9-year period, the percentage of infections with serovar types F and G increased (P = 0.007, P = 0.009), those with I and K decreased (P < 0.001, P = 0.008), and those with B, D, D-, E, H, Ia, and J remained stable. The age of those with positive Chlamydia cultures decreased (P < 0.001).

Conclusion: In this population, while the major serovars appeared stable over 9 years, significant changes in the distribution of minor serovars, especially G, were observed over time.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Age Factors
  • Chlamydia Infections / epidemiology*
  • Chlamydia Infections / etiology
  • Chlamydia Infections / microbiology*
  • Chlamydia trachomatis / classification*
  • Chlamydia trachomatis / isolation & purification
  • Female
  • Humans
  • Longitudinal Studies
  • Male
  • Prevalence
  • Risk Factors
  • Serotyping
  • Washington / epidemiology