Abstract: 【Abstract】 Chlamydia trachomatis （Ct） is the causative agent of bacterial sexually transmitted diseases （STDs） worldwide. The incidence of Ct infection has exceeded that of Neisseria gonorrhoeae, and becomes the highest in STDs in many countries. Ct infection can lead to urethritis, epididymitis, prostatitis and infertility in males, and cervicitis, endometritis, pelvic inflammatory disease, infertility in females, and neonatal conjunctivitis. Additionally, urogenital Ct infection is always ignored due to its concealed symptoms, leading to a long clinical course, recurrence or repeated infections. Furthermore, Ct infection can increase the risk of human immunodeficiency virus and human papilloma virus infections. Therefore, how to prevent and control the transmission of Ct has become one of the global public health issues. Currently, a growing body of researches have focused on the molecular epidemiological characteristics of Ct, which are aiming to identify the mutant strains, elaborate transmission dynamics, investigate the distribution of Ct serotypes in different populations, so as to provide molecular epidemiological evidence for the prevention and control of Ct infection. This review summarizes the epidemic status and research methods for molecular epidemiological characteristics of Ct, as well as application of Ct serotyping in clinical practice, providing references for the prevention, control and research of Ct infection.

Key words: Chlamydia trachomatis, Chlamydia infections; , Molecular epidemiology, Genotyping techniques, Multilocus sequence typing