<unk>  (), commonly known as<unk> , is a bacterium that causes<unk> , which can manifest in various ways, including: trachoma, lymphogranuloma venereum, nongonococcal urethritis, cervicitis, salpingitis, pelvic inflammatory disease.<unk>  is the most common infectious cause of blindness and the most common sexually transmitted bacterium. Different types of<unk>  cause different diseases. The most common strains cause disease in the genital tract, while other strains cause disease in the eye or lymph nodes. Like other<unk>  species, the<unk>  life cycle consists of two morphologically distinct life stages: elementary bodies and reticulate bodies. Elementary bodies are spore-like and infectious, whereas reticulate bodies are in the replicative stage and are seen only within host cells.
Chlamydia trachomatis
Neisseria gonorrhoeae
Trichomonas vaginalis
Mycoplasma genitalium
Haemophilus ducreyi
Treponema pallidum
Neisseria mucosa
Helicobacter suis