Chlamydia trachomatis

Embedded in a tissue

Chlamydia trachomatis is a strictly intracellular bacterium¹, which means that it needs, like viruses, eukaryotic² cells to multiply. It takes its name from the word “Chlamys”³, a tissue measuring 2 meters by 1 meter, used as a cloak in ancient Greece by the military. Chlamydia trachomatis is part of the Chlamydiales order, which contains a large diversity of bacteria including Rhabdochlamydia crassificans, Parachlamydia acanthamoebae, Chlamydia psitacci, which are all featured in the game Krobs (www.krobs.ch).

Chlamydia trachomatis can cause 2 types of diseases. On the one hand a genital infection, transmitted sexually, and on the other hand trachoma⁴, which represents the first cause of blindness⁵ in the world.

Genital infections

Genital chlamydia is usually symptomless. In men it is usually an infection of the urethra⁶ (called urethritis) and in women an infection of the cervix⁷ (called cervicitis). In women, urethritis very often accompanies the cervical infection. Thus, it is possible to make the diagnosis by PCR either from urine (which passes through the urethra from the bladder) or from cervico-vaginal smears. In men, PCR is usually performed on urines. Because of the absence of symptoms, Chlamydia trachomatis is the cause of a very large silent epidemic affecting about 5% of sexually active people in Europe.

Complications

Complications of genital chlamydia primarily impact women’s health, as chronic inflammation can lead to infertility, miscarriage and ectopic pregnancy⁸. The inflammation that initially affects the cervix⁷ can spread to the fallopian tubes, which will gradually become blocked. A partial obstruction will prevent the fertilized egg from descending to the uterus. When the obstruction is complete, the sperm will no longer be able to travel up the fallopian tubes⁹ to fertilize the egg, resulting in infertility.

An infection causing blindness

Trachoma is a disease that affects the cornea¹⁰ and the eyelids. The disease is most prevalent in sub-Saharan Africa. The agent of trachoma is transmitted mainly in childhood by hands from one person to another, or by flies. The chronic inflammation due to Chlamydia trachomatis will then cause scars on the eyelids. These scars will rub and inflame the eye, or more precisely the conjunctiva, eventually inducing an opacification of the cornea, making it blind. Chlamydia trachomatis is the leading cause of infectious blindness⁵ with more than 8 million people being blind worldwide.