Pathogen
Chlamydia trachomatis is a bacterium that causes a sexually transmitted infection known as chlamydia. It is a member of the Chlamydia genus, which consists of intracellular parasites that affect different species. As indicated by the name, Chlamydia trachomatis bacteria target cells as part of their two-stage lifecycle. First, an elementary body is formed, adapted to survival in the environment outside of a cell until it encounters one. The body then enters the cell and develops into its second stage, which parasitizes the cell and replicates itself numerous times. The incubation period for the bacterium is relatively slow and not well-researched, and, therefore, symptoms of the disease can appear several weeks after the initial exposure (“Chlamydia – CDC fact sheet,” 2016). The newly formed bodies then return to their elementary form, and the division continues until the cell ruptures, releasing them.
Transmission
As an STD, the most common form of transmission for Chlamydia trachomatis is via sexual contact. It can be transferred through semen as well as vaginal secretions, though secretions do not need to occur for transmission. “Chlamydia – CDC fact sheet” (2016) also describes the possibility of mother-to-child transmission while pregnant, with the infection occurring during the infant’s birth. The disease is not spread by animals, as they typically carry different species of the Chlamydia genus that are not compatible with humans. Environmental exposure is also unlikely, as the bacterium cannot survive outside of a host body and relies on people for transmission. To prevent transmission, the use of a latex male condom is advised, as it limits the contact between the partners’ genital areas during intercourse. Other options include being in a monogamous relationship with a partner who is known to be non-infected with the disease. Lastly, the most effective, though unlikely in practice, method of avoiding the condition is to abstain from oral, anal, or vaginal intercourse altogether.
Symptoms
In many cases, chlamydia infections are asymptomatic, not manifesting in physically detectable ways. An estimate given by “Chlamydia – CDC fact sheet” (2016) states that 10% of men and between 5% and 30% who are infected develop symptoms. If symptoms manifest, they tend to begin mildly and avoid detection until they develop into more severe issues. They depend on the location of the infection, possibly manifesting in genitalia or the rectum after the corresponding sexual act. Notable examples are cervicitis, urethritis, pelvic inflammatory disease, epididymitis, and proctitis, all associated with different symptoms depending on the person’s gender. One particularly dangerous area is the eyes, which can become blind after making contact with an infected genital fluid. On the other hand, “Chlamydia – CDC fact sheet” (2016) claims that, while oral sex can lead to chlamydia infections of the throat, they tend to be asymptomatic and not considered highly dangerous. In any case, over time, the infection typically becomes more severe and challenging to eradicate, spreading to new areas and leading to issues such as pregnancy terminations, perihepatitis, reactive arthritis, and others.
Demographics
Chlamydia trachomatis can affect any sexually active person, especially if they have multiple sexual partners or switch monogamous relationships rapidly. It is generally most prevalent in younger populations due to their high sexual activity rates and disregard for safety. “Chlamydia – CDC fact sheet” (2016) highlights the danger to teenage girls and young women with cervical ectopy as well as the lower access young people have to STD prevention services. Data tends to show higher chlamydia rates in women than in men overall, with “Chlamydia – CDC fact sheet” (2016) suggesting that one in twenty sexually active women aged 14-24 has the condition. The overall prevalence of Chlamydia trachomatis in 2016 is estimated at 3.7% in America by Rowley et al. (2019), as compared to 4.0% in Africa, 1.2% in Southeast Asia, 2.2% in Europe, and 2.7% overall throughout the world. As such, the risk of contracting the condition is relatively high in the United States compared to the rest of the world, making it a noteworthy concern.
Diagnosis and Treatment
Chlamydia can be diagnosed through a variety of different tests once its presence is suspected. The World Health Organization (2016) lists culture tests, direct immunofluorescence assays, enzyme-linked immunosorbent assays, and nucleic acid amplification tests as viable options. The last method is recommended particularly strongly due to their sensitive and specific nature, which can work with a variety of samples and identify the disease accurately. Once diagnosed, the treatment can begin, which mostly takes place via the administration of antibiotics. For uncomplicated genital chlamydia, the World Health Organization (2016) suggests azithromycin, doxycycline, tetracycline, erythromycin, or ofloxacin. Only doxycycline is suggested for oral usage in the case of an anorectal infection, though it should be avoided in the case of pregnancy. Other varieties of the condition warrant the use of specific appropriate antibiotics from the list described above. However, it should be noted that treatment practices for Chlamydia trachomatis are still under development as both new diagnosis methods and new medications for the disease emerge and are supported by high-quality evidence. As such, treatment approaches are likely to change in the future, and medical professionals should continually review best practices.
References
Chlamydia – CDC fact sheet (detailed). (2016). Web.
Rowley, J., Hoorn, S. V., Korenromp, E., Low, N., Unemo, M., Abu-Raddad, L. J., Chico, R. M., Smolak, A., Newman, L., Gottlieb, S., Thwin, S. S., Broutet, N., & Taylor, M. M. (2019). Chlamydia, gonorrhoea, trichomoniasis and syphilis: Global prevalence and incidence estimates, 2016. Web.
World Health Organization. (2016). WHO guidelines for the treatment of Chlamydia trachomatis. Web.